Merge remote-tracking branch 'origin/master' into check-updates

2016-11-23 14:45:55 +01:00 · 2016-11-23 14:45:55 +01:00 · 4c9bb5aa25
commit 4c9bb5aa25
parent bf9ed2d444 e7dd222142
69 changed files with 3820 additions and 342 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@ -1265,7 +1265,7 @@ dependencies = [
 [[package]]
 name = "parity-ui-precompiled"
 version = "1.4.0"
-source = "git+https://github.com/ethcore/js-precompiled.git#f46188126257e03c775e76a3cea82b5f70549400"
+source = "git+https://github.com/ethcore/js-precompiled.git#55741cc9850ad6dcbcb7e0a7ac16e805df85de9a"
 dependencies = [
 "parity-dapps-glue 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
--- a/ethcore/src/miner/miner.rs
+++ b/ethcore/src/miner/miner.rs
@ -580,29 +580,29 @@ impl Miner {
 		let gas_required = |tx: &SignedTransaction| tx.gas_required(&schedule).into();
 		let best_block_header: Header = ::rlp::decode(&chain.best_block_header());
 		transactions.into_iter()
-			.filter(|tx| match self.engine.verify_transaction_basic(tx, &best_block_header) {
-					Ok(()) => true,
+			.map(|tx| {
+				match self.engine.verify_transaction_basic(&tx, &best_block_header) {
 					Err(e) => {
 						debug!(target: "miner", "Rejected tx {:?} with invalid signature: {:?}", tx.hash(), e);
-						false
-					}
-				}
-			)
-			.map(|tx| {
-				let origin = accounts.as_ref().and_then(|accounts| {
-					tx.sender().ok().and_then(|sender| match accounts.contains(&sender) {
-						true => Some(TransactionOrigin::Local),
-						false => None,
-					})
-				}).unwrap_or(default_origin);
-
-				match origin {
-					TransactionOrigin::Local | TransactionOrigin::RetractedBlock => {
-						transaction_queue.add(tx, origin, &fetch_account, &gas_required)
+						Err(e)
+					},
+					Ok(()) => {
+						let origin = accounts.as_ref().and_then(|accounts| {
+							tx.sender().ok().and_then(|sender| match accounts.contains(&sender) {
+								true => Some(TransactionOrigin::Local),
+								false => None,
+							})
+						}).unwrap_or(default_origin);
+
+						match origin {
+							TransactionOrigin::Local | TransactionOrigin::RetractedBlock => {
+								transaction_queue.add(tx, origin, &fetch_account, &gas_required)
+							},
+							TransactionOrigin::External => {
+								transaction_queue.add_with_banlist(tx, &fetch_account, &gas_required)
+							}
+						}
 					},
-					TransactionOrigin::External => {
-						transaction_queue.add_with_banlist(tx, &fetch_account, &gas_required)
-					}
 				}
 			})
 			.collect()
--- a/ethcore/src/verification/queue/mod.rs
+++ b/ethcore/src/verification/queue/mod.rs
@ -35,6 +35,9 @@ pub mod kind;
 const MIN_MEM_LIMIT: usize = 16384;
 const MIN_QUEUE_LIMIT: usize = 512;

+// maximum possible number of verification threads.
+const MAX_VERIFIERS: usize = 8;
+
 /// Type alias for block queue convenience.
 pub type BlockQueue = VerificationQueue<self::kind::Blocks>;

@ -61,6 +64,37 @@ impl Default for Config {
 	}
 }

+struct VerifierHandle {
+	deleting: Arc<AtomicBool>,
+	sleep: Arc<AtomicBool>,
+	thread: JoinHandle<()>,
+}
+
+impl VerifierHandle {
+	// signal to the verifier thread that it should sleep.
+	fn sleep(&self) {
+		self.sleep.store(true, AtomicOrdering::SeqCst);
+	}
+
+	// signal to the verifier thread that it should wake up.
+	fn wake_up(&self) {
+		self.sleep.store(false, AtomicOrdering::SeqCst);
+		self.thread.thread().unpark();
+	}
+
+	// signal to the verifier thread that it should conclude its
+	// operations.
+	fn conclude(&self) {
+		self.wake_up();
+		self.deleting.store(true, AtomicOrdering::Release);
+	}
+
+	// join the verifier thread.
+	fn join(self) {
+		self.thread.join().expect("Verifier thread panicked");
+	}
+}
+
 /// An item which is in the process of being verified.
 pub struct Verifying<K: Kind> {
 	hash: H256,
@ -97,11 +131,12 @@ pub struct VerificationQueue<K: Kind> {
 	engine: Arc<Engine>,
 	more_to_verify: Arc<SCondvar>,
 	verification: Arc<Verification<K>>,
-	verifiers: Vec<JoinHandle<()>>,
+	verifiers: Mutex<(Vec<VerifierHandle>, usize)>,
 	deleting: Arc<AtomicBool>,
 	ready_signal: Arc<QueueSignal>,
 	empty: Arc<SCondvar>,
 	processing: RwLock<HashSet<H256>>,
+	ticks_since_adjustment: AtomicUsize,
 	max_queue_size: usize,
 	max_mem_use: usize,
 }
@ -157,6 +192,7 @@ struct Verification<K: Kind> {
 	more_to_verify: SMutex<()>,
 	empty: SMutex<()>,
 	sizes: Sizes,
+	check_seal: bool,
 }

 impl<K: Kind> VerificationQueue<K> {
@ -173,7 +209,8 @@ impl<K: Kind> VerificationQueue<K> {
 				unverified: AtomicUsize::new(0),
 				verifying: AtomicUsize::new(0),
 				verified: AtomicUsize::new(0),
-			}
+			},
+			check_seal: check_seal,
 		});
 		let more_to_verify = Arc::new(SCondvar::new());
 		let deleting = Arc::new(AtomicBool::new(false));
@ -185,44 +222,82 @@ impl<K: Kind> VerificationQueue<K> {
 		let empty = Arc::new(SCondvar::new());
 		let panic_handler = PanicHandler::new_in_arc();

-		let mut verifiers: Vec<JoinHandle<()>> = Vec::new();
-		let thread_count = max(::num_cpus::get(), 3) - 2;
-		for i in 0..thread_count {
-			let verification = verification.clone();
-			let engine = engine.clone();
-			let more_to_verify = more_to_verify.clone();
-			let ready_signal = ready_signal.clone();
-			let empty = empty.clone();
+		let max_verifiers = min(::num_cpus::get(), MAX_VERIFIERS);
+		let default_amount = max(::num_cpus::get(), 3) - 2;
+		let mut verifiers = Vec::with_capacity(max_verifiers);
+
+		debug!(target: "verification", "Allocating {} verifiers, {} initially active", max_verifiers, default_amount);
+
+		for i in 0..max_verifiers {
+			debug!(target: "verification", "Adding verification thread #{}", i);
+
 			let deleting = deleting.clone();
 			let panic_handler = panic_handler.clone();
-			verifiers.push(
-				thread::Builder::new()
-				.name(format!("Verifier #{}", i))
-				.spawn(move || {
-					panic_handler.catch_panic(move || {
-						VerificationQueue::verify(verification, engine, more_to_verify, ready_signal, deleting, empty, check_seal)
-					}).unwrap()
-				})
-				.expect("Error starting block verification thread")
-			);
+			let verification = verification.clone();
+			let engine = engine.clone();
+			let wait = more_to_verify.clone();
+			let ready = ready_signal.clone();
+			let empty = empty.clone();
+
+			// enable only the first few verifiers.
+			let sleep = if i < default_amount {
+				Arc::new(AtomicBool::new(false))
+			} else {
+				Arc::new(AtomicBool::new(true))
+			};
+
+			verifiers.push(VerifierHandle {
+				deleting: deleting.clone(),
+				sleep: sleep.clone(),
+				thread: thread::Builder::new()
+					.name(format!("Verifier #{}", i))
+					.spawn(move || {
+						panic_handler.catch_panic(move || {
+							VerificationQueue::verify(verification, engine, wait, ready, deleting, empty, sleep)
+						}).unwrap()
+					})
+					.expect("Failed to create verifier thread.")
+			});
 		}
+
 		VerificationQueue {
 			engine: engine,
 			panic_handler: panic_handler,
-			ready_signal: ready_signal.clone(),
-			more_to_verify: more_to_verify.clone(),
-			verification: verification.clone(),
-			verifiers: verifiers,
-			deleting: deleting.clone(),
+			ready_signal: ready_signal,
+			more_to_verify: more_to_verify,
+			verification: verification,
+			verifiers: Mutex::new((verifiers, default_amount)),
+			deleting: deleting,
 			processing: RwLock::new(HashSet::new()),
-			empty: empty.clone(),
+			empty: empty,
+			ticks_since_adjustment: AtomicUsize::new(0),
 			max_queue_size: max(config.max_queue_size, MIN_QUEUE_LIMIT),
 			max_mem_use: max(config.max_mem_use, MIN_MEM_LIMIT),
 		}
 	}

-	fn verify(verification: Arc<Verification<K>>, engine: Arc<Engine>, wait: Arc<SCondvar>, ready: Arc<QueueSignal>, deleting: Arc<AtomicBool>, empty: Arc<SCondvar>, check_seal: bool) {
+	fn verify(
+		verification: Arc<Verification<K>>,
+		engine: Arc<Engine>,
+		wait: Arc<SCondvar>,
+		ready: Arc<QueueSignal>,
+		deleting: Arc<AtomicBool>,
+		empty: Arc<SCondvar>,
+		sleep: Arc<AtomicBool>,
+	) {
 		while !deleting.load(AtomicOrdering::Acquire) {
+			{
+				while sleep.load(AtomicOrdering::SeqCst) {
+					trace!(target: "verification", "Verifier sleeping");
+					::std::thread::park();
+					trace!(target: "verification", "Verifier waking up");
+
+					if deleting.load(AtomicOrdering::Acquire) {
+						return;
+					}
+				}
+			}
+
 			{
 				let mut more_to_verify = verification.more_to_verify.lock().unwrap();

@ -255,7 +330,7 @@ impl<K: Kind> VerificationQueue<K> {
 			};

 			let hash = item.hash();
-			let is_ready = match K::verify(item, &*engine, check_seal) {
+			let is_ready = match K::verify(item, &*engine, verification.check_seal) {
 				Ok(verified) => {
 					let mut verifying = verification.verifying.lock();
 					let mut idx = None;
@ -302,9 +377,15 @@ impl<K: Kind> VerificationQueue<K> {
 		}
 	}

-	fn drain_verifying(verifying: &mut VecDeque<Verifying<K>>, verified: &mut VecDeque<K::Verified>, bad: &mut HashSet<H256>, sizes: &Sizes) {
+	fn drain_verifying(
+		verifying: &mut VecDeque<Verifying<K>>,
+		verified: &mut VecDeque<K::Verified>,
+		bad: &mut HashSet<H256>,
+		sizes: &Sizes,
+	) {
 		let mut removed_size = 0;
 		let mut inserted_size = 0;
+
 		while let Some(output) = verifying.front_mut().and_then(|x| x.output.take()) {
 			assert!(verifying.pop_front().is_some());
 			let size = output.heap_size_of_children();
@ -487,14 +568,85 @@ impl<K: Kind> VerificationQueue<K> {
 		}
 	}

-	/// Optimise memory footprint of the heap fields.
+	/// Optimise memory footprint of the heap fields, and adjust the number of threads
+	/// to better suit the workload.
 	pub fn collect_garbage(&self) {
-		{
-			self.verification.unverified.lock().shrink_to_fit();
+		// number of ticks to average queue stats over
+		// when deciding whether to change the number of verifiers.
+		#[cfg(not(test))]
+		const READJUSTMENT_PERIOD: usize = 12;
+
+		#[cfg(test)]
+		const READJUSTMENT_PERIOD: usize = 1;
+
+		let (u_len, v_len) = {
+			let u_len = {
+				let mut q = self.verification.unverified.lock();
+				q.shrink_to_fit();
+				q.len()
+			};
 			self.verification.verifying.lock().shrink_to_fit();
-			self.verification.verified.lock().shrink_to_fit();
-		}
+
+			let v_len = {
+				let mut q = self.verification.verified.lock();
+				q.shrink_to_fit();
+				q.len()
+			};
+
+			(u_len as isize, v_len as isize)
+		};
+
 		self.processing.write().shrink_to_fit();
+
+		if self.ticks_since_adjustment.fetch_add(1, AtomicOrdering::SeqCst) + 1 >= READJUSTMENT_PERIOD {
+			self.ticks_since_adjustment.store(0, AtomicOrdering::SeqCst);
+		} else {
+			return;
+		}
+
+		let current = self.verifiers.lock().1;
+
+		let diff = (v_len - u_len).abs();
+		let total = v_len + u_len;
+
+		self.scale_verifiers(
+			if u_len < 20 {
+				1
+			} else if diff <= total / 10 {
+				current
+			} else if v_len > u_len {
+				current - 1
+			} else {
+				current + 1
+			}
+		);
+	}
+
+	// wake up or sleep verifiers to get as close to the target as
+	// possible, never going over the amount of initially allocated threads
+	// or below 1.
+	fn scale_verifiers(&self, target: usize) {
+		let mut verifiers = self.verifiers.lock();
+		let &mut (ref mut verifiers, ref mut verifier_count) = &mut *verifiers;
+
+		let target = min(verifiers.len(), target);
+		let target = max(1, target);
+
+		debug!(target: "verification", "Scaling from {} to {} verifiers", verifier_count, target);
+
+		// scaling up
+		for i in *verifier_count..target {
+			debug!(target: "verification", "Waking up verifier {}", i);
+			verifiers[i].wake_up();
+		}
+
+		// scaling down.
+		for i in target..*verifier_count {
+			debug!(target: "verification", "Putting verifier {} to sleep", i);
+			verifiers[i].sleep();
+		}
+
+		*verifier_count = target;
 	}
 }

@ -509,10 +661,23 @@ impl<K: Kind> Drop for VerificationQueue<K> {
 		trace!(target: "shutdown", "[VerificationQueue] Closing...");
 		self.clear();
 		self.deleting.store(true, AtomicOrdering::Release);
-		self.more_to_verify.notify_all();
-		for t in self.verifiers.drain(..) {
-			t.join().unwrap();
+
+		let mut verifiers = self.verifiers.get_mut();
+		let mut verifiers = &mut verifiers.0;
+
+		// first pass to signal conclusion. must be done before
+		// notify or deadlock possible.
+		for handle in verifiers.iter() {
+			handle.conclude();
 		}
+
+		self.more_to_verify.notify_all();
+
+		// second pass to join.
+		for handle in verifiers.drain(..) {
+			handle.join();
+		}
+
 		trace!(target: "shutdown", "[VerificationQueue] Closed.");
 	}
 }
@ -611,4 +776,56 @@ mod tests {
 		}
 		assert!(queue.queue_info().is_full());
 	}
+
+	#[test]
+	fn scaling_limits() {
+		use super::MAX_VERIFIERS;
+
+		let queue = get_test_queue();
+		queue.scale_verifiers(MAX_VERIFIERS + 1);
+
+		assert!(queue.verifiers.lock().1 < MAX_VERIFIERS + 1);
+
+		queue.scale_verifiers(0);
+
+		assert!(queue.verifiers.lock().1 == 1);
+	}
+
+	#[test]
+	fn readjust_verifiers() {
+		let queue = get_test_queue();
+
+		// put all the verifiers to sleep to ensure 
+		// the test isn't timing sensitive.
+		let num_verifiers = {
+			let verifiers = queue.verifiers.lock();
+			for i in 0..verifiers.1 {
+				verifiers.0[i].sleep();
+			}
+
+			verifiers.1
+		};
+
+		for block in get_good_dummy_block_seq(5000) {
+			queue.import(Unverified::new(block)).expect("Block good by definition; qed");
+		}
+
+		// almost all unverified == bump verifier count.
+		queue.collect_garbage();
+		assert_eq!(queue.verifiers.lock().1, num_verifiers + 1);
+
+		// wake them up again and verify everything.
+		{
+			let verifiers = queue.verifiers.lock();
+			for i in 0..verifiers.1 {
+				verifiers.0[i].wake_up();
+			}
+		}
+
+		queue.flush();
+
+		// nothing to verify == use minimum number of verifiers.
+		queue.collect_garbage();
+		assert_eq!(queue.verifiers.lock().1, 1);
+	}
 }
--- a/js/package.json
+++ b/js/package.json
@ -1,6 +1,6 @@
 {
  "name": "parity.js",
-  "version": "0.2.61",
+  "version": "0.2.67",
  "main": "release/index.js",
  "jsnext:main": "src/index.js",
  "author": "Parity Team <admin@parity.io>",
@ -102,6 +102,7 @@
    "postcss-nested": "^1.0.0",
    "postcss-simple-vars": "^3.0.0",
    "raw-loader": "^0.5.1",
+    "react-addons-perf": "~15.3.2",
    "react-addons-test-utils": "~15.3.2",
    "react-copy-to-clipboard": "^4.2.3",
    "react-dom": "~15.3.2",
--- a/js/src/3rdparty/shapeshift/shapeshift.js
+++ b/js/src/3rdparty/shapeshift/shapeshift.js
@ -15,7 +15,8 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

 export default function (rpc) {
-  const subscriptions = [];
+  let subscriptions = [];
+  let pollStatusIntervalId = null;

  function getCoins () {
    return rpc.get('getcoins');
@ -45,6 +46,24 @@ export default function (rpc) {
      callback,
      idx
    });
+
+    // Only poll if there are subscriptions...
+    if (!pollStatusIntervalId) {
+      pollStatusIntervalId = setInterval(_pollStatus, 2000);
+    }
+  }
+
+  function unsubscribe (depositAddress) {
+    const newSubscriptions = []
+      .concat(subscriptions)
+      .filter((sub) => sub.depositAddress !== depositAddress);
+
+    subscriptions = newSubscriptions;
+
+    if (subscriptions.length === 0) {
+      clearInterval(pollStatusIntervalId);
+      pollStatusIntervalId = null;
+    }
  }

  function _getSubscriptionStatus (subscription) {
@ -81,13 +100,12 @@ export default function (rpc) {
    subscriptions.forEach(_getSubscriptionStatus);
  }

-  setInterval(_pollStatus, 2000);
-
  return {
    getCoins,
    getMarketInfo,
    getStatus,
    shift,
-    subscribe
+    subscribe,
+    unsubscribe
  };
 }
--- a/js/src/api/contract/contract.js
+++ b/js/src/api/contract/contract.js
@ -48,7 +48,11 @@ export default class Contract {
      this._instance[fn.signature] = fn;
    });

-    this._sendSubscriptionChanges();
+    this._subscribedToPendings = false;
+    this._pendingsSubscriptionId = null;
+
+    this._subscribedToBlock = false;
+    this._blockSubscriptionId = null;
  }

  get address () {
@ -239,44 +243,71 @@ export default class Contract {
    return event;
  }

-  subscribe (eventName = null, options = {}, callback) {
-    return new Promise((resolve, reject) => {
-      let event = null;
+  _findEvent (eventName = null) {
+    const event = eventName
+      ? this._events.find((evt) => evt.name === eventName)
+      : null;

-      if (eventName) {
-        event = this._events.find((evt) => evt.name === eventName);
+    if (eventName && !event) {
+      const events = this._events.map((evt) => evt.name).join(', ');
+      throw new Error(`${eventName} is not a valid eventName, subscribe using one of ${events} (or null to include all)`);
+    }

-        if (!event) {
-          const events = this._events.map((evt) => evt.name).join(', ');
-          reject(new Error(`${eventName} is not a valid eventName, subscribe using one of ${events} (or null to include all)`));
-          return;
-        }
-      }
+    return event;
+  }

-      return this._subscribe(event, options, callback).then(resolve).catch(reject);
+  _createEthFilter (event = null, _options) {
+    const optionTopics = _options.topics || [];
+    const signature = event && event.signature || null;
+
+    // If event provided, remove the potential event signature
+    // as the first element of the topics
+    const topics = signature
+      ? [ signature ].concat(optionTopics.filter((t, idx) => idx > 0 || t !== signature))
+      : optionTopics;
+
+    const options = Object.assign({}, _options, {
+      address: this._address,
+      topics
    });
+
+    return this._api.eth.newFilter(options);
+  }
+
+  subscribe (eventName = null, options = {}, callback) {
+    try {
+      const event = this._findEvent(eventName);
+      return this._subscribe(event, options, callback);
+    } catch (e) {
+      return Promise.reject(e);
+    }
  }

  _subscribe (event = null, _options, callback) {
    const subscriptionId = nextSubscriptionId++;
-    const options = Object.assign({}, _options, {
-      address: this._address,
-      topics: [event ? event.signature : null]
-    });
+    const { skipInitFetch } = _options;
+    delete _options['skipInitFetch'];

-    return this._api.eth
-      .newFilter(options)
+    return this
+      ._createEthFilter(event, _options)
      .then((filterId) => {
+        this._subscriptions[subscriptionId] = {
+          options: _options,
+          callback,
+          filterId
+        };
+
+        if (skipInitFetch) {
+          this._subscribeToChanges();
+          return subscriptionId;
+        }
+
        return this._api.eth
          .getFilterLogs(filterId)
          .then((logs) => {
            callback(null, this.parseEventLogs(logs));
-            this._subscriptions[subscriptionId] = {
-              options,
-              callback,
-              filterId
-            };

+            this._subscribeToChanges();
            return subscriptionId;
          });
      });
@ -285,19 +316,89 @@ export default class Contract {
  unsubscribe (subscriptionId) {
    return this._api.eth
      .uninstallFilter(this._subscriptions[subscriptionId].filterId)
-      .then(() => {
-        delete this._subscriptions[subscriptionId];
-      })
      .catch((error) => {
        console.error('unsubscribe', error);
+      })
+      .then(() => {
+        delete this._subscriptions[subscriptionId];
+        this._unsubscribeFromChanges();
      });
  }

-  _sendSubscriptionChanges = () => {
+  _subscribeToChanges = () => {
    const subscriptions = Object.values(this._subscriptions);
-    const timeout = () => setTimeout(this._sendSubscriptionChanges, 1000);

-    Promise
+    const pendingSubscriptions = subscriptions
+      .filter((s) => s.options.toBlock && s.options.toBlock === 'pending');
+
+    const otherSubscriptions = subscriptions
+      .filter((s) => !(s.options.toBlock && s.options.toBlock === 'pending'));
+
+    if (pendingSubscriptions.length > 0 && !this._subscribedToPendings) {
+      this._subscribedToPendings = true;
+      this._subscribeToPendings();
+    }
+
+    if (otherSubscriptions.length > 0 && !this._subscribedToBlock) {
+      this._subscribedToBlock = true;
+      this._subscribeToBlock();
+    }
+  }
+
+  _unsubscribeFromChanges = () => {
+    const subscriptions = Object.values(this._subscriptions);
+
+    const pendingSubscriptions = subscriptions
+      .filter((s) => s.options.toBlock && s.options.toBlock === 'pending');
+
+    const otherSubscriptions = subscriptions
+      .filter((s) => !(s.options.toBlock && s.options.toBlock === 'pending'));
+
+    if (pendingSubscriptions.length === 0 && this._subscribedToPendings) {
+      this._subscribedToPendings = false;
+      clearTimeout(this._pendingsSubscriptionId);
+    }
+
+    if (otherSubscriptions.length === 0 && this._subscribedToBlock) {
+      this._subscribedToBlock = false;
+      this._api.unsubscribe(this._blockSubscriptionId);
+    }
+  }
+
+  _subscribeToBlock = () => {
+    this._api
+      .subscribe('eth_blockNumber', (error) => {
+        if (error) {
+          console.error('::_subscribeToBlock', error, error && error.stack);
+        }
+
+        const subscriptions = Object.values(this._subscriptions)
+          .filter((s) => !(s.options.toBlock && s.options.toBlock === 'pending'));
+
+        this._sendSubscriptionChanges(subscriptions);
+      })
+      .then((blockSubId) => {
+        this._blockSubscriptionId = blockSubId;
+      })
+      .catch((e) => {
+        console.error('::_subscribeToBlock', e, e && e.stack);
+      });
+  }
+
+  _subscribeToPendings = () => {
+    const subscriptions = Object.values(this._subscriptions)
+      .filter((s) => s.options.toBlock && s.options.toBlock === 'pending');
+
+    const timeout = () => setTimeout(() => this._subscribeToPendings(), 1000);
+
+    this._sendSubscriptionChanges(subscriptions)
+      .then(() => {
+        this._pendingsSubscriptionId = timeout();
+      });
+  }
+
+  _sendSubscriptionChanges = (subscriptions) => {
+    return Promise
      .all(
        subscriptions.map((subscription) => {
          return this._api.eth.getFilterChanges(subscription.filterId);
@ -315,12 +416,9 @@ export default class Contract {
            console.error('_sendSubscriptionChanges', error);
          }
        });
-
-        timeout();
      })
      .catch((error) => {
        console.error('_sendSubscriptionChanges', error);
-        timeout();
      });
  }
 }
--- a/js/src/api/contract/contract.spec.js
+++ b/js/src/api/contract/contract.spec.js
@ -437,6 +437,7 @@ describe('api/contract/Contract', () => {
        ]
      }
    ];
+
    const logs = [{
      address: '0x22bff18ec62281850546a664bb63a5c06ac5f76c',
      blockHash: '0xa9280530a3b47bee2fc80f2862fd56502ae075350571d724d6442ea4c597347b',
@ -450,6 +451,7 @@ describe('api/contract/Contract', () => {
      transactionHash: '0xca16f537d761d13e4e80953b754e2b15541f267d6cad9381f750af1bae1e4917',
      transactionIndex: '0x0'
    }];
+
    const parsed = [{
      address: '0x22bfF18ec62281850546a664bb63a5C06AC5F76C',
      blockHash: '0xa9280530a3b47bee2fc80f2862fd56502ae075350571d724d6442ea4c597347b',
@ -466,11 +468,13 @@ describe('api/contract/Contract', () => {
        sender: { type: 'address', value: '0x63Cf90D3f0410092FC0fca41846f596223979195' }
      },
      topics: [
-        '0x954ba6c157daf8a26539574ffa64203c044691aa57251af95f4b48d85ec00dd5', '0x0000000000000000000000000000000000000000000000000001000000004fe0'
+        '0x954ba6c157daf8a26539574ffa64203c044691aa57251af95f4b48d85ec00dd5',
+        '0x0000000000000000000000000000000000000000000000000001000000004fe0'
      ],
      transactionHash: '0xca16f537d761d13e4e80953b754e2b15541f267d6cad9381f750af1bae1e4917',
      transactionIndex: new BigNumber(0)
    }];
+
    let contract;

    beforeEach(() => {
@ -496,18 +500,19 @@ describe('api/contract/Contract', () => {
        scope = mockHttp([
          { method: 'eth_newFilter', reply: { result: '0x123' } },
          { method: 'eth_getFilterLogs', reply: { result: logs } },
+          { method: 'eth_getFilterChanges', reply: { result: logs } },
          { method: 'eth_newFilter', reply: { result: '0x123' } },
          { method: 'eth_getFilterLogs', reply: { result: logs } }
        ]);
        cbb = sinon.stub();
        cbe = sinon.stub();

-        return contract.subscribe('Message', {}, cbb);
+        return contract.subscribe('Message', { toBlock: 'pending' }, cbb);
      });

      it('sets the subscriptionId returned', () => {
        return contract
-          .subscribe('Message', {}, cbe)
+          .subscribe('Message', { toBlock: 'pending' }, cbe)
          .then((subscriptionId) => {
            expect(subscriptionId).to.equal(1);
          });
@ -515,7 +520,7 @@ describe('api/contract/Contract', () => {

      it('creates a new filter and retrieves the logs on it', () => {
        return contract
-          .subscribe('Message', {}, cbe)
+          .subscribe('Message', { toBlock: 'pending' }, cbe)
          .then((subscriptionId) => {
            expect(scope.isDone()).to.be.true;
          });
@ -523,7 +528,7 @@ describe('api/contract/Contract', () => {

      it('returns the logs to the callback', () => {
        return contract
-          .subscribe('Message', {}, cbe)
+          .subscribe('Message', { toBlock: 'pending' }, cbe)
          .then((subscriptionId) => {
            expect(cbe).to.have.been.calledWith(null, parsed);
          });
--- a/js/src/api/format/input.js
+++ b/js/src/api/format/input.js
@ -15,6 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

 import BigNumber from 'bignumber.js';
+import { range } from 'lodash';

 import { isArray, isHex, isInstanceOf, isString } from '../util/types';

@ -50,14 +51,19 @@ export function inHash (hash) {
  return inHex(hash);
 }

+export function pad (input, length) {
+  const value = inHex(input).substr(2, length * 2);
+  return '0x' + value + range(length * 2 - value.length).map(() => '0').join('');
+}
+
 export function inTopics (_topics) {
  let topics = (_topics || [])
-    .filter((topic) => topic)
-    .map(inHex);
+    .filter((topic) => topic === null || topic)
+    .map((topic) => topic === null ? null : pad(topic, 32));

-  while (topics.length < 4) {
-    topics.push(null);
-  }
+  // while (topics.length < 4) {
+  //   topics.push(null);
+  // }

  return topics;
 }
--- a/js/src/api/util/format.js
+++ b/js/src/api/util/format.js
@ -29,3 +29,7 @@ export function hex2Ascii (_hex) {

  return str;
 }
+
+export function asciiToHex (string) {
+  return '0x' + string.split('').map((s) => s.charCodeAt(0).toString(16)).join('');
+}
--- a/js/src/api/util/index.js
+++ b/js/src/api/util/index.js
@ -16,7 +16,7 @@

 import { isAddress as isAddressValid, toChecksumAddress } from '../../abi/util/address';
 import { decodeCallData, decodeMethodInput, methodToAbi } from './decode';
-import { bytesToHex, hex2Ascii } from './format';
+import { bytesToHex, hex2Ascii, asciiToHex } from './format';
 import { fromWei, toWei } from './wei';
 import { sha3 } from './sha3';
 import { isArray, isFunction, isHex, isInstanceOf, isString } from './types';
@ -31,6 +31,7 @@ export default {
  isString,
  bytesToHex,
  hex2Ascii,
+  asciiToHex,
  createIdentityImg,
  decodeCallData,
  decodeMethodInput,
--- a/js/src/contracts/sms-verification.js
+++ b/js/src/contracts/sms-verification.js
@ -19,17 +19,34 @@ export const checkIfVerified = (contract, account) => {
 };

 export const checkIfRequested = (contract, account) => {
+  let subId = null;
+  let resolved = false;
+
  return new Promise((resolve, reject) => {
-    contract.subscribe('Requested', {
-      fromBlock: 0, toBlock: 'pending'
-    }, (err, logs) => {
-      if (err) {
-        return reject(err);
-      }
-      const e = logs.find((l) => {
-        return l.type === 'mined' && l.params.who && l.params.who.value === account;
+    contract
+      .subscribe('Requested', {
+        fromBlock: 0, toBlock: 'pending'
+      }, (err, logs) => {
+        if (err) {
+          return reject(err);
+        }
+        const e = logs.find((l) => {
+          return l.type === 'mined' && l.params.who && l.params.who.value === account;
+        });
+
+        resolve(e ? e.transactionHash : false);
+        resolved = true;
+
+        if (subId) {
+          contract.unsubscribe(subId);
+        }
+      })
+      .then((_subId) => {
+        subId = _subId;
+
+        if (resolved) {
+          contract.unsubscribe(subId);
+        }
      });
-      resolve(e ? e.transactionHash : false);
-    });
  });
 };
--- a/js/src/dapps/dappreg.html
+++ b/js/src/dapps/dappreg.html
@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <link rel="icon" href="/parity-logo-black-no-text.png" type="image/png">
+    <title>Dapp Registry</title>
+  </head>
+  <body>
+    <div id="container"></div>
+    <script src="vendor.js"></script>
+    <script src="commons.js"></script>
+    <script src="/parity-utils/parity.js"></script>
+    <script src="dappreg.js"></script>
+  </body>
+</html>
--- a/js/src/dapps/dappreg.js
+++ b/js/src/dapps/dappreg.js
@ -0,0 +1,35 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React from 'react';
+import ReactDOM from 'react-dom';
+import injectTapEventPlugin from 'react-tap-event-plugin';
+import { useStrict } from 'mobx';
+
+injectTapEventPlugin();
+useStrict(true);
+
+import Application from './dappreg/Application';
+
+import '../../assets/fonts/Roboto/font.css';
+import '../../assets/fonts/RobotoMono/font.css';
+import './style.css';
+import './dappreg.html';
+
+ReactDOM.render(
+  <Application />,
+  document.querySelector('#container')
+);
--- a/js/src/dapps/dappreg/Application/application.css
+++ b/js/src/dapps/dappreg/Application/application.css
@ -0,0 +1,58 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.body {
+  color: #333;
+  background: #eee;
+  padding: 4.5em 0;
+  text-align: center;
+}
+
+.apps {
+  background: #fff;
+  border-radius: 0.5em;
+  margin: 0 auto;
+  max-width: 980px;
+  padding: 1.5em;
+  text-align: left;
+}
+
+.footer {
+  font-size: 0.75em;
+  margin: 1em;
+  padding: 1.5em;
+  text-align: center;
+}
+
+.header {
+  background: #44e;
+  border-radius: 0 0 0.25em 0.25em;
+  color: #fff;
+  left: 0;
+  padding: 1em;
+  position: fixed;
+  right: 0;
+  top: 0;
+  z-index: 25;
+}
+
+.loading {
+  text-align: center;
+  padding-top: 5em;
+  font-size: 2em;
+  color: #999;
+}
--- a/js/src/dapps/dappreg/Application/application.js
+++ b/js/src/dapps/dappreg/Application/application.js
@ -0,0 +1,64 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import DappsStore from '../dappsStore';
+
+import ButtonBar from '../ButtonBar';
+import Dapp from '../Dapp';
+import ModalDelete from '../ModalDelete';
+import ModalRegister from '../ModalRegister';
+import ModalUpdate from '../ModalUpdate';
+import SelectDapp from '../SelectDapp';
+import Warning from '../Warning';
+import styles from './application.css';
+
+@observer
+export default class Application extends Component {
+  dappsStore = DappsStore.instance();
+
+  render () {
+    if (this.dappsStore.isLoading) {
+      return (
+        <div className={ styles.loading }>
+          Loading application
+        </div>
+      );
+    }
+
+    return (
+      <div className={ styles.body }>
+        <div className={ styles.header }>
+          DAPP REGISTRY, a global view of distributed applications available on the network. Putting the puzzle together.
+        </div>
+        <div className={ styles.apps }>
+          <SelectDapp />
+          <ButtonBar />
+          <Dapp />
+        </div>
+        <div className={ styles.footer }>
+          { this.dappsStore.count } applications registered, { this.dappsStore.ownedCount } owned by user
+        </div>
+        <Warning />
+        <ModalDelete />
+        <ModalRegister />
+        <ModalUpdate />
+      </div>
+    );
+  }
+}
--- a/js/src/dapps/dappreg/Application/index.js
+++ b/js/src/dapps/dappreg/Application/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './application';
--- a/js/src/dapps/dappreg/Button/button.css
+++ b/js/src/dapps/dappreg/Button/button.css
@ -0,0 +1,38 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.button {
+  background: #44e;
+  border: none;
+  border-radius: 0.25em;
+  color: #fff;
+  cursor: pointer;
+  font-size: 1em;
+  margin: 1em 0.375em;
+  opacity: 0.85;
+  padding: 0.75em 2em;
+
+  &[disabled] {
+    opacity: 0.5;
+    cursor: default;
+    background: #aaa;
+  }
+
+  &[data-warning="true"] {
+    background: #e44;
+  }
+}
--- a/js/src/dapps/dappreg/Button/button.js
+++ b/js/src/dapps/dappreg/Button/button.js
@ -0,0 +1,52 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component, PropTypes } from 'react';
+
+import styles from './button.css';
+
+export default class Button extends Component {
+  static propTypes = {
+    className: PropTypes.string,
+    disabled: PropTypes.bool,
+    label: PropTypes.string.isRequired,
+    warning: PropTypes.bool,
+    onClick: PropTypes.func.isRequired
+  }
+
+  render () {
+    const { className, disabled, label, warning } = this.props;
+    const classes = `${styles.button} ${className}`;
+
+    return (
+      <button
+        className={ classes }
+        data-warning={ warning }
+        disabled={ disabled }
+        onClick={ this.onClick }>
+        { label }
+      </button>
+    );
+  }
+
+  onClick = (event) => {
+    if (this.props.disabled) {
+      return;
+    }
+
+    this.props.onClick(event);
+  }
+}
--- a/js/src/dapps/dappreg/Button/index.js
+++ b/js/src/dapps/dappreg/Button/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './button';
--- a/js/src/dapps/dappreg/ButtonBar/buttonBar.css
+++ b/js/src/dapps/dappreg/ButtonBar/buttonBar.css
@ -0,0 +1,21 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.buttonbar {
+  text-align: center;
+  margin: 1em 0 0 0;
+}
--- a/js/src/dapps/dappreg/ButtonBar/buttonBar.js
+++ b/js/src/dapps/dappreg/ButtonBar/buttonBar.js
@ -0,0 +1,101 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import DappsStore from '../dappsStore';
+import ModalStore from '../modalStore';
+
+import Button from '../Button';
+import styles from './buttonBar.css';
+
+@observer
+export default class ButtonBar extends Component {
+  dappsStore = DappsStore.instance();
+  modalStore = ModalStore.instance();
+
+  render () {
+    let buttons = [];
+
+    if (this.dappsStore.isEditing || this.dappsStore.isNew) {
+      buttons = [
+        <Button
+          key='cancel'
+          label='Cancel'
+          warning
+          onClick={ this.onCancelClick } />,
+        <Button
+          key='save'
+          label={ this.dappsStore.isNew ? 'Register' : 'Update' }
+          disabled={ !this.dappsStore.canSave }
+          onClick={ this.onSaveClick } />
+      ];
+    } else {
+      buttons = [
+        <Button
+          key='delete'
+          label='Delete'
+          warning
+          disabled={ !this.dappsStore.currentApp.isOwner && !this.dappsStore.isContractOwner }
+          onClick={ this.onDeleteClick } />,
+        <Button
+          key='edit'
+          label='Edit'
+          disabled={ !this.dappsStore.currentApp.isOwner }
+          onClick={ this.onEditClick } />,
+        <Button
+          key='new'
+          label='New'
+          onClick={ this.onNewClick } />
+      ];
+    }
+
+    return (
+      <div className={ styles.buttonbar }>
+        { buttons }
+      </div>
+    );
+  }
+
+  onCancelClick = () => {
+    if (this.dappsStore.isEditing) {
+      this.dappsStore.setEditing(false);
+    } else {
+      this.dappsStore.setNew(false);
+    }
+  }
+
+  onDeleteClick = () => {
+    this.modalStore.showDelete();
+  }
+
+  onEditClick = () => {
+    this.dappsStore.setEditing(true);
+  }
+
+  onNewClick = () => {
+    this.dappsStore.setNew(true);
+  }
+
+  onSaveClick = () => {
+    if (this.dappsStore.isEditing) {
+      this.modalStore.showUpdate();
+    } else {
+      this.modalStore.showRegister();
+    }
+  }
+}
--- a/js/src/dapps/dappreg/ButtonBar/index.js
+++ b/js/src/dapps/dappreg/ButtonBar/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './buttonBar';
--- a/js/src/dapps/dappreg/Dapp/dapp.css
+++ b/js/src/dapps/dappreg/Dapp/dapp.css
@ -0,0 +1,19 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.app {
+}
--- a/js/src/dapps/dappreg/Dapp/dapp.js
+++ b/js/src/dapps/dappreg/Dapp/dapp.js
@ -0,0 +1,162 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import { api } from '../parity';
+import DappsStore from '../dappsStore';
+
+import Input from '../Input';
+import SelectAccount from '../SelectAccount';
+import styles from './dapp.css';
+
+@observer
+export default class Dapp extends Component {
+  dappsStore = DappsStore.instance();
+
+  render () {
+    const app = this.dappsStore.isNew || this.dappsStore.isEditing
+      ? this.dappsStore.wipApp
+      : this.dappsStore.currentApp;
+
+    return (
+      <div className={ styles.app }>
+        { this.dappsStore.isNew ? this.renderOwnerSelect(app) : this.renderOwnerStatic(app) }
+        { this.renderInputs(app) }
+      </div>
+    );
+  }
+
+  renderInputs (app) {
+    if (this.dappsStore.isNew) {
+      return null;
+    }
+
+    return [
+      this.renderHashInput(app, 'image', 'Image hash, as generated by Githubhint', true),
+      this.renderHashInput(app, 'manifest', 'Manifest hash, as generated by Githubhint'),
+      this.renderHashInput(app, 'content', 'Content hash, as generated by Githubhint')
+    ];
+  }
+
+  renderOwnerSelect (app) {
+    const overlayImage = (
+      <img
+        className={ styles.overlayImage }
+        src={ api.util.createIdentityImg(this.dappsStore.currentAccount.address, 4) } />
+    );
+
+    return (
+      <Input
+        hint={ this.dappsStore.currentAccount.address }
+        label='Owner, select the application owner and editor'
+        overlay={ overlayImage }>
+        <SelectAccount />
+      </Input>
+    );
+  }
+
+  renderOwnerStatic (app) {
+    const overlayImage = (
+      <img
+        className={ styles.overlayImage }
+        src={ api.util.createIdentityImg(app.owner, 4) } />
+    );
+
+    return (
+      <Input
+        hint={ app.owner }
+        label='Owner, the application owner and editor'
+        overlay={ overlayImage }>
+        <input value={ app.ownerName } readOnly />
+      </Input>
+    );
+  }
+
+  renderHashInput (app, type, label, withImage = false) {
+    const onChange = (event) => this.onChangeHash(event, type);
+    const hash = app[`${type}Hash`];
+
+    let overlayImage = null;
+    if (withImage && hash) {
+      overlayImage = (
+        <img
+          className={ styles.overlayImage }
+          src={ `/api/content/${hash.substr(2)}` } />
+      );
+    }
+
+    return (
+      <Input
+        hint={ app[`${type}Error`] || app[`${type}Url`] || '...' }
+        label={ label }
+        key={ `${type}Edit` }
+        overlay={ overlayImage }>
+        <input
+          value={ app[`${type}Hash`] || '' }
+          data-dirty={ app[`${type}Changed`] }
+          data-error={ !!app[`${type}Error`] }
+          readOnly={ !this.dappsStore.isEditing && !this.dappsStore.isNew }
+          onChange={ onChange } />
+      </Input>
+    );
+  }
+
+  onChangeHash (event, type) {
+    if (!this.dappsStore.isNew && !this.dappsStore.isEditing) {
+      return;
+    }
+
+    const hash = event.target.value;
+    let changed = false;
+    let url = null;
+
+    if (this.dappsStore.isNew) {
+      if (hash && hash.length) {
+        changed = true;
+      }
+    } else {
+      if (this.dappsStore.currentApp[`${type}Hash`] !== hash) {
+        changed = true;
+      } else {
+        url = this.dappsStore.currentApp[`${type}Url`];
+      }
+    }
+
+    this.dappsStore.editWip({
+      [`${type}Changed`]: changed,
+      [`${type}Error`]: null,
+      [`${type}Hash`]: hash,
+      [`${type}Url`]: changed ? 'Resolving url from hash' : url
+    });
+
+    if (changed) {
+      if (hash.length) {
+        this.dappsStore
+          .lookupHash(hash)
+          .then((url) => {
+            this.dappsStore.editWip({
+              [`${type}Error`]: url ? null : 'Unable to resolve url',
+              [`${type}Url`]: url
+            });
+          });
+      } else {
+        this.dappsStore.editWip({ [`${type}Url`]: null });
+      }
+    }
+  }
+}
--- a/js/src/dapps/dappreg/Dapp/index.js
+++ b/js/src/dapps/dappreg/Dapp/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './dapp';
--- a/js/src/dapps/dappreg/Input/index.js
+++ b/js/src/dapps/dappreg/Input/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './input';
--- a/js/src/dapps/dappreg/Input/input.css
+++ b/js/src/dapps/dappreg/Input/input.css
@ -0,0 +1,92 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.input {
+  position: relative;
+
+  input, select {
+    background: rgba(255, 255, 255, 0.85);
+    border: 4px solid rgba(223, 223, 223, 0.85);
+    border-radius: 0.25em;
+    box-sizing: border-box;
+    color: #333;
+    font-size: 1em;
+    margin: 0.25em 0 0.25em 0;
+    padding: 0.5em 0.5em 1.5em 0.5em;
+    width: 100%;
+  }
+
+  input {
+    padding-bottom: 1.5em;
+
+    &[data-dirty="true"] {
+      background: rgba(255, 255, 203, 0.85);
+      border-color: rgba(203, 203, 151, 0.85);
+    }
+
+    &[data-error="true"] {
+      background: rgba(255, 223, 223, 0.85) !important;
+      border-color: rgba(223, 191, 191, 0.85) !important;
+    }
+
+    &[readonly] {
+      background: rgba(239, 239, 239, 0.85);
+      border-color: rgba(223, 223, 223, 0.85);
+    }
+  }
+
+  label {
+    color: #888;
+    display: block;
+    font-size: 0.75em;
+    margin-top: 1.5em;
+  }
+
+  select {
+    -moz-appearance: none;
+    -webkit-appearance: none;
+    appearance: none;
+    height: 58px;
+
+    &[disabled] {
+      background: rgba(239, 239, 239, 0.85);
+      border-color: rgba(223, 223, 223, 0.85);
+    }
+  }
+
+  .hint {
+    color: #888;
+    display: block;
+    font-size: 0.75em;
+    position: absolute;
+    right: 52px;
+    text-align: right;
+    top: 52px;
+  }
+
+  .overlay {
+    right: 10px;
+    position: absolute;
+    top: 30px;
+
+    img {
+      border-radius: 50%;
+      height: 32px;
+      width: 32px;
+    }
+  }
+}
--- a/js/src/dapps/dappreg/Input/input.js
+++ b/js/src/dapps/dappreg/Input/input.js
@ -0,0 +1,47 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component, PropTypes } from 'react';
+
+import styles from './input.css';
+
+export default class Input extends Component {
+  static propTypes = {
+    children: PropTypes.node.isRequired,
+    hint: PropTypes.string,
+    label: PropTypes.string.isRequired,
+    overlay: PropTypes.node
+  }
+
+  render () {
+    const { children, hint, label, overlay } = this.props;
+
+    return (
+      <div className={ styles.input }>
+        <label>
+          { label }
+        </label>
+        { children }
+        <div className={ styles.hint }>
+          { hint }
+        </div>
+        <div className={ styles.overlay }>
+          { overlay }
+        </div>
+      </div>
+    );
+  }
+}
--- a/js/src/dapps/dappreg/Modal/index.js
+++ b/js/src/dapps/dappreg/Modal/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './modal';
--- a/js/src/dapps/dappreg/Modal/modal.css
+++ b/js/src/dapps/dappreg/Modal/modal.css
@ -0,0 +1,116 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.modal {
+  .body {
+    bottom: 0;
+    left: 0;
+    position: fixed;
+    right: 0;
+    top: 0;
+    text-align: center;
+    z-index: 50;
+
+    .dialog {
+      background: #fff;
+      border-radius: 0 0 0.25em 0.25em;
+      margin: 0 auto;
+      max-width: 840px;
+      text-align: left;
+
+      .content {
+        line-height: 1.5em;
+        padding: 2em;
+        text-align: center;
+
+        .section {
+          margin: 0;
+          padding: 0;
+
+          &.error {
+            color: #f44;
+          }
+        }
+
+        .section+.section {
+          margin-top: 1em;
+        }
+      }
+
+      .footer {
+        padding: 0.5em 1.625em;
+        text-align: right;
+      }
+
+      .header {
+        background: #44e;
+        color: #fff;
+        opacity: 0.85;
+        padding: 1em;
+
+        &.error {
+          background: #e44;
+        }
+      }
+    }
+  }
+
+  .overlay {
+    background: rgba(204, 204, 204, 0.7);
+    bottom: 0;
+    left: 0;
+    position: fixed;
+    right: 0;
+    top: 0;
+    z-index: 49;
+  }
+}
+
+.account {
+  div {
+    display: inline-block;
+    vertical-align: top;
+  }
+
+  img {
+    border-radius: 50%;
+    margin-right: 0.5em;
+  }
+}
+
+.hint {
+  display: block !important;
+  color: #888;
+  font-size: 0.75em;
+  margin-top: -0.5em;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.center {
+  text-align: center;
+}
+
+.heading {
+  color: #888;
+  font-size: 0.75em;
+}
+
+.light {
+  color: #888;
+}
--- a/js/src/dapps/dappreg/Modal/modal.js
+++ b/js/src/dapps/dappreg/Modal/modal.js
@ -0,0 +1,66 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component, PropTypes } from 'react';
+
+import styles from './modal.css';
+
+export default class Modal extends Component {
+  static propTypes = {
+    buttons: PropTypes.node,
+    children: PropTypes.node,
+    error: PropTypes.object,
+    header: PropTypes.string
+  }
+
+  render () {
+    const { children, buttons, error, header } = this.props;
+
+    return (
+      <div className={ styles.modal }>
+        <div className={ styles.overlay } />
+        <div className={ styles.body }>
+          <div className={ styles.dialog }>
+            <div className={ `${styles.header} ${error ? styles.error : ''}` }>
+              { header }
+            </div>
+            <div className={ styles.content }>
+              { error ? this.renderError() : children }
+            </div>
+            <div className={ styles.footer }>
+              { buttons }
+            </div>
+          </div>
+        </div>
+      </div>
+    );
+  }
+
+  renderError () {
+    const { error } = this.props;
+
+    return (
+      <div>
+        <div className={ styles.section }>
+          Your operation failed to complete sucessfully. The following error was returned:
+        </div>
+        <div className={ `${styles.section} ${styles.error}` }>
+          { error.toString() }
+        </div>
+      </div>
+    );
+  }
+}
--- a/js/src/dapps/dappreg/ModalDelete/index.js
+++ b/js/src/dapps/dappreg/ModalDelete/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './modalDelete';
--- a/js/src/dapps/dappreg/ModalDelete/modalDelete.js
+++ b/js/src/dapps/dappreg/ModalDelete/modalDelete.js
@ -0,0 +1,159 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import { api } from '../parity';
+import DappsStore from '../dappsStore';
+import ModalStore from '../modalStore';
+
+import Button from '../Button';
+import Modal from '../Modal';
+
+import styles from '../Modal/modal.css';
+
+const HEADERS = [
+  'Error During Deletion',
+  'Confirm Application Deletion',
+  'Waiting for Signer Confirmation',
+  'Waiting for Transaction Receipt',
+  'Deletion Completed'
+];
+const STEP_ERROR = 0;
+const STEP_CONFIRM = 1;
+const STEP_SIGNER = 2;
+const STEP_TXRECEIPT = 3;
+const STEP_DONE = 4;
+
+@observer
+export default class ModalDelete extends Component {
+  dappsStore = DappsStore.instance();
+  modalStore = ModalStore.instance();
+
+  render () {
+    if (!this.modalStore.showingDelete) {
+      return null;
+    }
+
+    return (
+      <Modal
+        buttons={ this.renderButtons() }
+        error={ this.modalStore.errorDelete }
+        header={ HEADERS[this.modalStore.stepDelete] }>
+        { this.renderStep() }
+      </Modal>
+    );
+  }
+
+  renderButtons () {
+    switch (this.modalStore.stepDelete) {
+      case STEP_ERROR:
+      case STEP_DONE:
+        return [
+          <Button
+            key='close'
+            label='Close'
+            onClick={ this.onClickClose } />
+        ];
+      case STEP_CONFIRM:
+        return [
+          <Button
+            key='cancel'
+            label='No, Cancel'
+            onClick={ this.onClickClose } />,
+          <Button
+            key='delete'
+            label='Yes, Delete'
+            warning
+            onClick={ this.onClickYes } />
+        ];
+      default:
+        return null;
+    }
+  }
+
+  renderStep () {
+    switch (this.modalStore.stepDelete) {
+      case STEP_CONFIRM:
+        return this.renderStepConfirm();
+      case STEP_SIGNER:
+        return this.renderStepWait('Waiting for transaction confirmation in the Parity secure signer');
+      case STEP_TXRECEIPT:
+        return this.renderStepWait('Waiting for the transaction receipt from the network');
+      case STEP_DONE:
+        return this.renderStepCompleted();
+      default:
+        return null;
+    }
+  }
+
+  renderStepCompleted () {
+    return (
+      <div>
+        <div className={ styles.section }>
+          Your application has been removed from the registry.
+        </div>
+      </div>
+    );
+  }
+
+  renderStepConfirm () {
+    return (
+      <div>
+        <div className={ styles.section }>
+          You are about to remove a distributed application from the registry, the details of this application is given below. Removal does not return any fees, however the application will not be available to users anymore.
+        </div>
+        <div className={ styles.section }>
+          <div className={ styles.heading }>
+            Owner account
+          </div>
+          <div className={ styles.account }>
+            <img src={ api.util.createIdentityImg(this.dappsStore.currentApp.owner, 3) } />
+            <div>{ this.dappsStore.currentApp.ownerName }</div>
+            <div className={ styles.address }>{ this.dappsStore.currentApp.owner }</div>
+          </div>
+        </div>
+        <div className={ styles.section }>
+          <div className={ styles.heading }>
+            Application identifier
+          </div>
+          <div>
+            { this.dappsStore.currentApp.id }
+          </div>
+        </div>
+      </div>
+    );
+  }
+
+  renderStepWait (waitingFor) {
+    return (
+      <div>
+        <div className={ styles.section }>
+          { waitingFor }
+        </div>
+      </div>
+    );
+  }
+
+  onClickClose = () => {
+    this.modalStore.hideDelete();
+  }
+
+  onClickYes = () => {
+    this.modalStore.doDelete();
+  }
+}
--- a/js/src/dapps/dappreg/ModalRegister/index.js
+++ b/js/src/dapps/dappreg/ModalRegister/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './modalRegister';
--- a/js/src/dapps/dappreg/ModalRegister/modalRegister.js
+++ b/js/src/dapps/dappreg/ModalRegister/modalRegister.js
@ -0,0 +1,159 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import { api } from '../parity';
+import DappsStore from '../dappsStore';
+import ModalStore from '../modalStore';
+
+import Button from '../Button';
+import Modal from '../Modal';
+
+import styles from '../Modal/modal.css';
+
+const HEADERS = [
+  'Error During Registration',
+  'Confirm Application Registration',
+  'Waiting for Signer Confirmation',
+  'Waiting for Transaction Receipt',
+  'Registration Completed'
+];
+const STEP_ERROR = 0;
+const STEP_CONFIRM = 1;
+const STEP_SIGNER = 2;
+const STEP_TXRECEIPT = 3;
+const STEP_DONE = 4;
+
+@observer
+export default class ModalRegister extends Component {
+  dappsStore = DappsStore.instance();
+  modalStore = ModalStore.instance();
+
+  render () {
+    if (!this.modalStore.showingRegister) {
+      return null;
+    }
+
+    return (
+      <Modal
+        buttons={ this.renderButtons() }
+        error={ this.modalStore.errorRegister }
+        header={ HEADERS[this.modalStore.stepRegister] }>
+        { this.renderStep() }
+      </Modal>
+    );
+  }
+
+  renderButtons () {
+    switch (this.modalStore.stepRegister) {
+      case STEP_ERROR:
+      case STEP_DONE:
+        return [
+          <Button
+            key='close'
+            label='Close'
+            onClick={ this.onClickClose } />
+        ];
+      case STEP_CONFIRM:
+        return [
+          <Button
+            key='cancel'
+            label='No, Cancel'
+            onClick={ this.onClickClose } />,
+          <Button
+            key='register'
+            label='Yes, Register'
+            warning
+            onClick={ this.onClickConfirmYes } />
+        ];
+      default:
+        return null;
+    }
+  }
+
+  renderStep () {
+    switch (this.modalStore.stepRegister) {
+      case STEP_CONFIRM:
+        return this.renderStepConfirm();
+      case STEP_SIGNER:
+        return this.renderStepWait('Waiting for transaction confirmation in the Parity secure signer');
+      case STEP_TXRECEIPT:
+        return this.renderStepWait('Waiting for the transaction receipt from the network');
+      case STEP_DONE:
+        return this.renderStepCompleted();
+      default:
+        return null;
+    }
+  }
+
+  renderStepCompleted () {
+    return (
+      <div>
+        <div className={ styles.section }>
+          Your application has been registered in the registry.
+        </div>
+      </div>
+    );
+  }
+
+  renderStepConfirm () {
+    return (
+      <div>
+        <div className={ styles.section }>
+          You are about to register a new distributed application on the network, the details of this application is given below. This will require a non-refundable fee of { api.util.fromWei(this.dappsStore.fee).toFormat(3) }<small>ETH</small>.
+        </div>
+        <div className={ styles.section }>
+          <div className={ styles.heading }>
+            Selected owner account
+          </div>
+          <div className={ styles.account }>
+            <img src={ api.util.createIdentityImg(this.dappsStore.currentAccount.address, 3) } />
+            <div>{ this.dappsStore.currentAccount.name }</div>
+            <div className={ styles.hint }>{ this.dappsStore.currentAccount.address }</div>
+          </div>
+        </div>
+        <div className={ styles.section }>
+          <div className={ styles.heading }>
+            Unique assigned application identifier
+          </div>
+          <div>
+            { this.dappsStore.wipApp.id }
+          </div>
+        </div>
+      </div>
+    );
+  }
+
+  renderStepWait (waitingFor) {
+    return (
+      <div>
+        <div className={ styles.section }>
+          { waitingFor }
+        </div>
+      </div>
+    );
+  }
+
+  onClickClose = () => {
+    this.modalStore.hideRegister();
+  }
+
+  onClickConfirmYes = () => {
+    this.modalStore.doRegister();
+  }
+}
--- a/js/src/dapps/dappreg/ModalUpdate/index.js
+++ b/js/src/dapps/dappreg/ModalUpdate/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './modalUpdate';
--- a/js/src/dapps/dappreg/ModalUpdate/modalUpdate.js
+++ b/js/src/dapps/dappreg/ModalUpdate/modalUpdate.js
@ -0,0 +1,169 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import DappsStore from '../dappsStore';
+import ModalStore from '../modalStore';
+
+import Button from '../Button';
+import Modal from '../Modal';
+
+import styles from '../Modal/modal.css';
+
+const HEADERS = [
+  'Error During Update',
+  'Confirm Application Update',
+  'Waiting for Signer Confirmation',
+  'Waiting for Transaction Receipt',
+  'Update Completed'
+];
+const STEP_ERROR = 0;
+const STEP_CONFIRM = 1;
+const STEP_SIGNER = 2;
+const STEP_TXRECEIPT = 3;
+const STEP_DONE = 4;
+
+@observer
+export default class ModalUpdate extends Component {
+  dappsStore = DappsStore.instance();
+  modalStore = ModalStore.instance();
+
+  render () {
+    if (!this.modalStore.showingUpdate) {
+      return null;
+    }
+
+    return (
+      <Modal
+        buttons={ this.renderButtons() }
+        error={ this.modalStore.errorUpdate }
+        header={ HEADERS[this.modalStore.stepUpdate] }>
+        { this.renderStep() }
+      </Modal>
+    );
+  }
+
+  renderButtons () {
+    switch (this.modalStore.stepUpdate) {
+      case STEP_ERROR:
+      case STEP_DONE:
+        return [
+          <Button
+            key='close'
+            label='Close'
+            onClick={ this.onClickClose } />
+        ];
+      case STEP_CONFIRM:
+        return [
+          <Button
+            key='cancel'
+            label='No, Cancel'
+            onClick={ this.onClickClose } />,
+          <Button
+            key='delete'
+            label='Yes, Update'
+            warning
+            onClick={ this.onClickYes } />
+        ];
+      default:
+        return null;
+    }
+  }
+
+  renderStep () {
+    switch (this.modalStore.stepUpdate) {
+      case STEP_CONFIRM:
+        return this.renderStepConfirm();
+      case STEP_SIGNER:
+        return this.renderStepWait('Waiting for transaction confirmation in the Parity secure signer');
+      case STEP_TXRECEIPT:
+        return this.renderStepWait('Waiting for the transaction receipt from the network');
+      case STEP_DONE:
+        return this.renderStepCompleted();
+      default:
+        return null;
+    }
+  }
+
+  renderStepCompleted () {
+    return (
+      <div>
+        <div className={ styles.section }>
+          Your application metadata has been updated in the registry.
+        </div>
+      </div>
+    );
+  }
+
+  renderStepConfirm () {
+    return (
+      <div>
+        <div className={ styles.section }>
+          You are about to update the application details in the registry, the details of these updates are given below. Please note that each update will generate a seperate transaction.
+        </div>
+        <div className={ styles.section }>
+          <div className={ styles.heading }>
+            Application identifier
+          </div>
+          <div>
+            { this.dappsStore.wipApp.id }
+          </div>
+        </div>
+        { this.renderChanges() }
+      </div>
+    );
+  }
+
+  renderChanges () {
+    return ['content', 'image', 'manifest']
+      .filter((type) => this.dappsStore.wipApp[`${type}Changed`])
+      .map((type) => {
+        return (
+          <div className={ styles.section } key={ `${type}Update` }>
+            <div className={ styles.heading }>
+              Updates to { type } hash
+            </div>
+            <div>
+              <div>{ this.dappsStore.wipApp[`${type}Hash`] || '(removed)' }</div>
+              <div className={ styles.hint }>
+                { this.dappsStore.wipApp[`${type}Url`] || 'current url to be removed from registry' }
+              </div>
+            </div>
+          </div>
+        );
+      });
+  }
+
+  renderStepWait (waitingFor) {
+    return (
+      <div>
+        <div className={ styles.section }>
+          { waitingFor }
+        </div>
+      </div>
+    );
+  }
+
+  onClickClose = () => {
+    this.modalStore.hideUpdate();
+  }
+
+  onClickYes = () => {
+    this.modalStore.doUpdate();
+  }
+}
--- a/js/src/dapps/dappreg/SelectAccount/index.js
+++ b/js/src/dapps/dappreg/SelectAccount/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './selectAccount';
--- a/js/src/dapps/dappreg/SelectAccount/selectAccount.js
+++ b/js/src/dapps/dappreg/SelectAccount/selectAccount.js
@ -0,0 +1,49 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import DappsStore from '../dappsStore';
+
+@observer
+export default class SelectAccount extends Component {
+  dappsStore = DappsStore.instance();
+
+  render () {
+    return (
+      <select
+        value={ this.dappsStore.currentAccount.address }
+        onChange={ this.onSelect }>
+        { this.renderOptions() }
+      </select>
+    );
+  }
+
+  renderOptions () {
+    return this.dappsStore.accounts.map((account) => {
+      return (
+        <option value={ account.address } key={ account.address }>
+          { account.name }
+        </option>
+      );
+    });
+  }
+
+  onSelect = (event) => {
+    this.dappsStore.setCurrentAccount(event.target.value);
+  }
+}
--- a/js/src/dapps/dappreg/SelectDapp/index.js
+++ b/js/src/dapps/dappreg/SelectDapp/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './selectDapp';
--- a/js/src/dapps/dappreg/SelectDapp/selectDapp.js
+++ b/js/src/dapps/dappreg/SelectDapp/selectDapp.js
@ -0,0 +1,76 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import DappsStore from '../dappsStore';
+
+import Input from '../Input';
+
+@observer
+export default class SelectDapp extends Component {
+  dappsStore = DappsStore.instance();
+
+  render () {
+    if (this.dappsStore.isNew) {
+      return (
+        <Input
+          hint='...'
+          label='Application Id, the unique assigned identifier'>
+          <input value={ this.dappsStore.wipApp.id } readOnly />
+        </Input>
+      );
+    }
+
+    let overlayImg = null;
+    if (this.dappsStore.currentApp.imageHash) {
+      overlayImg = (
+        <img src={ `/api/content/${this.dappsStore.currentApp.imageHash.substr(2)}` } />
+      );
+    }
+
+    return (
+      <Input
+        hint={ this.dappsStore.currentApp.id }
+        label='Application, the actual application details to show below'
+        overlay={ overlayImg }>
+        <select
+          disabled={ this.dappsStore.isEditing }
+          value={ this.dappsStore.currentApp.id }
+          onChange={ this.onSelect }>
+          { this.renderOptions() }
+        </select>
+      </Input>
+    );
+  }
+
+  renderOptions () {
+    return this.dappsStore.apps.map((app) => {
+      return (
+        <option
+          value={ app.id }
+          key={ app.id }>
+          { app.name }
+        </option>
+      );
+    });
+  }
+
+  onSelect = (event) => {
+    this.dappsStore.setCurrentApp(event.target.value);
+  }
+}
--- a/js/src/dapps/dappreg/Warning/index.js
+++ b/js/src/dapps/dappreg/Warning/index.js
@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './warning';
--- a/js/src/dapps/dappreg/Warning/warning.css
+++ b/js/src/dapps/dappreg/Warning/warning.css
@ -0,0 +1,36 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.warning {
+  background: #f44;
+  border-top-right-radius: 0.25em;
+  bottom: 0;
+  color: #fff;
+  cursor: pointer;
+  font-size: 0.75em;
+  left: 0;
+  line-height: 1.5em;
+  opacity: 1;
+  padding: 1.5em;
+  position: fixed;
+  max-width: 540px;
+  z-index: 100;
+
+  div+div {
+    margin-top: 1.5em;
+  }
+}
--- a/js/src/dapps/dappreg/Warning/warning.js
+++ b/js/src/dapps/dappreg/Warning/warning.js
@ -0,0 +1,51 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component } from 'react';
+import { observer } from 'mobx-react';
+
+import { api } from '../parity';
+import DappsStore from '../dappsStore';
+import ModalStore from '../modalStore';
+
+import styles from './warning.css';
+
+@observer
+export default class Warning extends Component {
+  dappsStore = DappsStore.instance();
+  modalStore = ModalStore.instance();
+
+  render () {
+    if (!this.modalStore.showingWarning) {
+      return null;
+    }
+
+    return (
+      <div className={ styles.warning } onClick={ this.onClose }>
+        <div>
+          WARNING: Registering a dapp is for developers only. Please ensure you understand the steps needed to develop and deploy applications, should you wish to use this dapp for anything apart from queries.
+        </div>
+        <div>
+          A non-refundable fee of { api.util.fromWei(this.dappsStore.fee).toFormat(3) }<small>ETH</small> is required for any registration.
+        </div>
+      </div>
+    );
+  }
+
+  onClose = () => {
+    this.modalStore.hideWarning();
+  }
+}
--- a/js/src/dapps/dappreg/dappsStore.js
+++ b/js/src/dapps/dappreg/dappsStore.js
@ -0,0 +1,482 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import BigNumber from 'bignumber.js';
+import { action, computed, observable, transaction } from 'mobx';
+
+import * as abis from '../../contracts/abi';
+import builtins from '../../views/Dapps/builtin.json';
+
+import { api } from './parity';
+
+let instance = null;
+
+export default class DappsStore {
+  @observable accounts = [];
+  @observable addresses = [];
+  @observable apps = [];
+  @observable contractOwner = null;
+  @observable currentAccount = null;
+  @observable currentApp = null;
+  @observable count = 0;
+  @observable fee = new BigNumber(0);
+  @observable isContractOwner = false;
+  @observable isEditing = false;
+  @observable isLoading = true;
+  @observable isNew = false;
+  @observable wipApp = null;
+
+  _startTime = Date.now();
+
+  constructor () {
+    this._loadDapps();
+  }
+
+  static instance () {
+    if (!instance) {
+      instance = new DappsStore();
+    }
+
+    return instance;
+  }
+
+  @computed get canSave () {
+    const app = this.wipApp;
+
+    const hasError = app.contentError || app.imageError || app.manifestError;
+    const isDirty = this.isNew || app.contentChanged || app.imageChanged || app.manifestChanged;
+    const isEditMode = this.isEditing || this.isNew;
+
+    return isEditMode && isDirty && !hasError;
+  }
+
+  @computed get isCurrentEditable () {
+    return !!this.accounts.find((account) => account.address === this.currentApp.owner);
+  }
+
+  @computed get ownedCount () {
+    return (this.apps.filter((app) => app.isOwner) || []).length;
+  }
+
+  @action copyToWip = () => {
+    let wipApp;
+
+    if (this.isNew) {
+      wipApp = {
+        id: api.util.sha3(`${this._startTime}_${Date.now()}`),
+        contentHash: null,
+        contentUrl: null,
+        imageHash: null,
+        imageUrl: null,
+        manifestHash: null,
+        manifestUrl: null
+      };
+    } else {
+      const app = this.currentApp;
+
+      wipApp = {
+        id: app.id,
+        contentHash: app.contentHash,
+        contentUrl: app.contentUrl,
+        imageHash: app.imageHash,
+        imageUrl: app.imageUrl,
+        manifestHash: app.manifestHash,
+        manifestUrl: app.manifestUrl,
+        owner: app.owner,
+        ownerName: app.ownerName
+      };
+    }
+
+    this.wipApp = Object.assign(wipApp, {
+      contentChanged: false,
+      contentError: null,
+      imageChanged: false,
+      imageError: null,
+      manifestChanged: false,
+      manifestError: null
+    });
+
+    return this.wipApp;
+  }
+
+  @action editWip = (details) => {
+    if (this.isNew || this.isEditing) {
+      transaction(() => {
+        Object
+          .keys(details)
+          .forEach((key) => {
+            this.wipApp[key] = details[key];
+          });
+      });
+    }
+
+    return this.wipApp;
+  }
+
+  @action sortApps = (apps = this.apps) => {
+    transaction(() => {
+      const ownApps = apps
+        .filter((app) => app.isOwner)
+        .sort((a, b) => a.name.localeCompare(b.name));
+      const otherApps = apps
+        .filter((app) => !app.isOwner)
+        .sort((a, b) => a.name.localeCompare(b.name));
+
+      this.apps = ownApps.concat(otherApps);
+      this.currentApp = this.apps[0];
+    });
+  }
+
+  @action setApps = (apps) => {
+    this.sortApps(apps.filter((app) => {
+      const bnid = new BigNumber(app.id);
+      return bnid.gt(0);
+    }));
+
+    return this.apps;
+  }
+
+  @action _addApp = (app) => {
+    transaction(() => {
+      this.setApps(this.apps.concat([app]));
+      this.setCurrentApp(app.id);
+    });
+  }
+
+  @action addApp = (appId, account) => {
+    this
+      ._loadDapp({
+        id: appId,
+        isOwner: true,
+        name: `- ${appId}`,
+        owner: account.address,
+        ownerName: account.name
+      })
+      .then(this._addApp);
+  }
+
+  @action refreshApp = (appId) => {
+    this._loadDapp(this.apps.find((app) => app.id === appId));
+  }
+
+  @action removeApp = (appId) => {
+    this.setApps(this.apps.filter((app) => app.id !== appId));
+  }
+
+  @action setAppInfo = (app, info) => {
+    transaction(() => {
+      Object.keys(info).forEach((key) => {
+        app[key] = info[key];
+      });
+    });
+
+    return app;
+  }
+
+  @action setAccounts = (accountsInfo) => {
+    transaction(() => {
+      this.addresses = Object
+        .keys(accountsInfo)
+        .map((address) => {
+          const account = accountsInfo[address];
+          account.address = address;
+          return account;
+        });
+
+      this.accounts = this.addresses.filter((account) => account.uuid);
+      this.currentAccount = this.accounts[0];
+    });
+
+    return this.accounts;
+  }
+
+  @action setContractOwner = (contractOwner) => {
+    transaction(() => {
+      this.contractOwner = contractOwner;
+      this.isContractOwner = !!this.accounts.find((account) => account.address === contractOwner);
+    });
+    return contractOwner;
+  }
+
+  @action setCurrentApp = (id) => {
+    this.currentApp = this.apps.find((app) => app.id === id);
+    return this.currentApp;
+  }
+
+  @action setCurrentAccount = (address) => {
+    this.currentAccount = this.accounts.find((account) => account.address === address);
+    return this.currentAccount;
+  }
+
+  @action setCount = (count) => {
+    this.count = count;
+    return count;
+  }
+
+  @action setEditing = (mode) => {
+    transaction(() => {
+      this.isEditing = mode;
+      this.copyToWip();
+    });
+
+    return mode;
+  }
+
+  @action setFee = (fee) => {
+    this.fee = fee;
+    return fee;
+  }
+
+  @action setLoading = (loading) => {
+    this.isLoading = loading;
+    return loading;
+  }
+
+  @action setNew = (mode) => {
+    transaction(() => {
+      this.isNew = mode;
+      this.copyToWip();
+    });
+
+    return mode;
+  }
+
+  lookupHash (hash) {
+    return this._retrieveUrl(hash);
+  }
+
+  _getCount () {
+    return this._instanceReg
+      .count.call()
+      .then((count) => {
+        this.setCount(count.toNumber());
+      })
+      .catch((error) => {
+        console.error('Store:getCount', error);
+      });
+  }
+
+  _getFee () {
+    return this._instanceReg
+      .fee.call()
+      .then(this.setFee)
+      .catch((error) => {
+        console.error('Store:getFee', error);
+      });
+  }
+
+  _getOwner () {
+    return this._instanceReg
+      .owner.call()
+      .then(this.setContractOwner)
+      .catch((error) => {
+        console.error('Store:getOwner', error);
+      });
+  }
+
+  _loadDapps () {
+    return this._loadRegistry()
+      .then(() => Promise.all([
+        this._attachContracts(),
+        this._loadAccounts()
+      ]))
+      .then(() => Promise.all([
+        this._getCount(),
+        this._getFee(),
+        this._getOwner()
+      ]))
+      .then(() => {
+        const promises = [];
+
+        for (let index = 0; index < this.count; index++) {
+          promises.push(this._instanceReg.at.call({}, [index]));
+        }
+
+        return Promise.all(promises);
+      })
+      .then((appsInfo) => {
+        return Promise.all(
+          this
+            .setApps(appsInfo.map(([appId, owner]) => {
+              const isOwner = !!this.accounts.find((account) => account.address === owner);
+              const account = this.addresses.find((account) => account.address === owner);
+              const id = api.util.bytesToHex(appId);
+
+              return {
+                id,
+                owner,
+                ownerName: account ? account.name : owner,
+                isOwner,
+                name: `- ${id}`
+              };
+            }))
+            .map(this._loadDapp)
+        );
+      })
+      .then(() => {
+        this.sortApps();
+        this.setLoading(this.count === 0);
+      })
+      .catch((error) => {
+        console.error('Store:loadDapps', error);
+      });
+  }
+
+  _loadDapp = (app) => {
+    return Promise
+      .all([
+        this._loadMeta(app.id, 'CONTENT'),
+        this._loadMeta(app.id, 'IMG'),
+        this._loadMeta(app.id, 'MANIFEST')
+      ])
+      .then(([contentHash, imageHash, manifestHash]) => {
+        return Promise
+          .all([
+            this._retrieveUrl(contentHash),
+            this._retrieveUrl(imageHash),
+            this._retrieveUrl(manifestHash)
+          ])
+          .then(([contentUrl, imageUrl, manifestUrl]) => {
+            return this
+              ._loadManifest(app.id, manifestHash)
+              .then((manifest) => {
+                this.setAppInfo(app, {
+                  manifest,
+                  manifestHash,
+                  manifestUrl,
+                  contentHash,
+                  contentUrl,
+                  imageHash,
+                  imageUrl,
+                  name: (manifest && manifest.name) || `- ${app.id}`
+                });
+
+                return app;
+              });
+          });
+      })
+      .catch((error) => {
+        console.error('Store:loadDapp', error);
+      });
+  }
+
+  _loadMeta (appId, key) {
+    return this._instanceReg
+      .meta.call({}, [appId, key])
+      .then((meta) => {
+        const hash = api.util.bytesToHex(meta);
+        const bnhash = new BigNumber(hash);
+
+        return bnhash.gt(0)
+          ? hash
+          : null;
+      })
+      .catch((error) => {
+        console.error('Store:loadMeta', error);
+        return null;
+      });
+  }
+
+  _loadManifest (appId, manifestHash) {
+    const builtin = builtins.find((app) => app.id === appId);
+
+    if (builtin) {
+      return Promise.resolve(builtin);
+    } else if (!manifestHash) {
+      return Promise.resolve(null);
+    }
+
+    return fetch(`/api/content/${manifestHash.substr(2)}/`, { redirect: 'follow', mode: 'cors' })
+      .then((response) => {
+        return response.ok
+          ? response.json()
+          : null;
+      })
+      .catch((error) => {
+        console.error('Store:loadManifest', error);
+        return null;
+      });
+  }
+
+  _retrieveUrl (urlHash) {
+    if (!urlHash) {
+      return Promise.resolve(null);
+    }
+
+    return this._instanceGhh
+      .entries.call({}, [urlHash])
+      .then(([repo, _commit, owner]) => {
+        const bnowner = new BigNumber(owner);
+
+        if (bnowner.eq(0)) {
+          return null;
+        }
+
+        const commit = api.util.bytesToHex(_commit);
+        const bncommit = new BigNumber(commit);
+
+        if (bncommit.eq(0)) {
+          return repo;
+        } else {
+          return `https://codeload.github.com/${repo}/zip/${commit.substr(2)}`;
+        }
+      })
+      .catch((error) => {
+        console.error('Store:retriveUrl', error);
+        return null;
+      });
+  }
+
+  _loadAccounts () {
+    return api.parity
+      .accounts()
+      .then(this.setAccounts)
+      .catch((error) => {
+        console.error('Store:loadAccounts', error);
+      });
+  }
+
+  _loadRegistry () {
+    return api.parity
+      .registryAddress()
+      .then((registryAddress) => {
+        console.log(`the registry was found at ${registryAddress}`);
+        this._registry = api.newContract(abis.registry, registryAddress).instance;
+      })
+      .catch((error) => {
+        console.error('Store:loadRegistry', error);
+      });
+  }
+
+  _attachContracts () {
+    return Promise
+      .all([
+        this._registry.getAddress.call({}, [api.util.sha3('dappreg'), 'A']),
+        this._registry.getAddress.call({}, [api.util.sha3('githubhint'), 'A'])
+      ])
+      .then(([dappregAddress, ghhAddress]) => {
+        console.log(`dappreg was found at ${dappregAddress}`);
+        this._contractReg = api.newContract(abis.dappreg, dappregAddress);
+        this._instanceReg = this._contractReg.instance;
+        console.log(`githubhint was found at ${ghhAddress}`);
+        this._contractGhh = api.newContract(abis.githubhint, ghhAddress);
+        this._instanceGhh = this._contractGhh.instance;
+      })
+      .catch((error) => {
+        console.error('Store:attachContract', error);
+      });
+  }
+}
--- a/js/src/dapps/dappreg/modalStore.js
+++ b/js/src/dapps/dappreg/modalStore.js
@ -0,0 +1,266 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import { action, observable, transaction } from 'mobx';
+
+import { trackRequest } from './parity';
+import DappsStore from './dappsStore';
+
+let instance = null;
+
+export default class ModalStore {
+  @observable errorDelete = null;
+  @observable errorRegister = null;
+  @observable errorUpdate = null;
+  @observable stepDelete = 0;
+  @observable stepRegister = 0;
+  @observable stepUpdate = 0;
+  @observable showingDelete = false;
+  @observable showingRegister = false;
+  @observable showingUpdate = false;
+  @observable showingWarning = true;
+
+  _dappsStore = DappsStore.instance();
+
+  static instance () {
+    if (!instance) {
+      instance = new ModalStore();
+    }
+
+    return instance;
+  }
+
+  @action setDeleteError (error) {
+    transaction(() => {
+      this.setDeleteStep(0);
+      this.errorDelete = error;
+    });
+  }
+
+  @action setDeleteStep (step) {
+    this.stepDelete = step;
+  }
+
+  @action showDelete () {
+    transaction(() => {
+      this.setDeleteStep(1);
+      this.errorDelete = null;
+      this.showingDelete = true;
+    });
+  }
+
+  @action hideDelete () {
+    this.showingDelete = false;
+  }
+
+  @action setRegisterError (error) {
+    transaction(() => {
+      this.setRegisterStep(0);
+      this.errorRegister = error;
+    });
+  }
+
+  @action setRegisterStep (step) {
+    this.stepRegister = step;
+  }
+
+  @action showRegister () {
+    transaction(() => {
+      this.setRegisterStep(1);
+      this.errorRegister = null;
+      this.showingRegister = true;
+    });
+  }
+
+  @action hideRegister () {
+    transaction(() => {
+      this._dappsStore.setEditing(false);
+      this._dappsStore.setNew(false);
+      this.showingRegister = false;
+    });
+  }
+
+  @action setUpdateError (error) {
+    transaction(() => {
+      this.setUpdateStep(0);
+      this.errorUpdate = error;
+    });
+  }
+
+  @action setUpdateStep (step) {
+    this.stepUpdate = step;
+  }
+
+  @action showUpdate () {
+    transaction(() => {
+      this.setUpdateStep(1);
+      this.errorUpdate = null;
+      this.showingUpdate = true;
+    });
+  }
+
+  @action hideUpdate () {
+    transaction(() => {
+      this._dappsStore.setEditing(false);
+      this._dappsStore.setNew(false);
+      this.showingUpdate = false;
+    });
+  }
+
+  @action hideWarning () {
+    this.showingWarning = false;
+  }
+
+  doDelete () {
+    this.setDeleteStep(2);
+
+    const appId = this._dappsStore.currentApp.id;
+    const values = [appId];
+    const options = {
+      from: this._dappsStore.currentApp.isOwner ? this._dappsStore.currentApp.owner : this._dappsStore.contractOwner
+    };
+
+    console.log('ModalStore:doDelete', `performing deletion for ${appId} from ${options.from}`);
+
+    this._dappsStore._instanceReg
+      .unregister.estimateGas(options, values)
+      .then((gas) => {
+        const newGas = gas.mul(1.2);
+
+        console.log('ModalStore:doDelete', `gas estimated as ${gas.toFormat(0)}, setting to ${newGas.toFormat(0)}`);
+
+        options.gas = newGas.toFixed(0);
+
+        const request = this._dappsStore._instanceReg.unregister.postTransaction(options, values);
+        const statusCallback = (error, status) => {
+          if (error) {
+          } else if (status.signerRequestId) {
+          } else if (status.transactionHash) {
+            this.setDeleteStep(3);
+          } else if (status.transactionReceipt) {
+            this.setDeleteStep(4);
+            this._dappsStore.removeApp(appId);
+          }
+        };
+
+        return trackRequest(request, statusCallback);
+      })
+      .catch((error) => {
+        console.error('ModalStore:doDelete', error);
+        this.setDeleteError(error);
+      });
+  }
+
+  doRegister () {
+    this.setRegisterStep(2);
+
+    const appId = this._dappsStore.wipApp.id;
+    const values = [appId];
+    const options = {
+      from: this._dappsStore.currentAccount.address,
+      value: this._dappsStore.fee
+    };
+
+    console.log('ModalStore:doRegister', `performing registration for ${appId} from ${this._dappsStore.currentAccount.address}`);
+
+    this._dappsStore._instanceReg
+      .register.estimateGas(options, values)
+      .then((gas) => {
+        const newGas = gas.mul(1.2);
+
+        console.log('ModalStore:doRegister', `gas estimated as ${gas.toFormat(0)}, setting to ${newGas.toFormat(0)}`);
+
+        options.gas = newGas.toFixed(0);
+
+        const request = this._dappsStore._instanceReg.register.postTransaction(options, values);
+        const statusCallback = (error, status) => {
+          if (error) {
+          } else if (status.signerRequestId) {
+          } else if (status.transactionHash) {
+            this.setRegisterStep(3);
+          } else if (status.transactionReceipt) {
+            this.setRegisterStep(4);
+            this._dappsStore.addApp(appId, this._dappsStore.currentAccount);
+          }
+        };
+
+        return trackRequest(request, statusCallback);
+      })
+      .catch((error) => {
+        console.error('ModalStore:doRegister', error);
+        this.setRegisterError(error);
+      });
+  }
+
+  doUpdate () {
+    this.setUpdateStep(2);
+
+    const appId = this._dappsStore.wipApp.id;
+    const options = {
+      from: this._dappsStore.wipApp.owner
+    };
+    const types = {
+      'content': 'CONTENT',
+      'image': 'IMG',
+      'manifest': 'MANIFEST'
+    };
+    const values = Object
+      .keys(types)
+      .filter((type) => this._dappsStore.wipApp[`${type}Changed`])
+      .map((type) => {
+        return [appId, types[type], this._dappsStore.wipApp[`${type}Hash`] || '0x0'];
+      });
+
+    console.log('ModalStore:doUpdate', `performing updates for ${appId} from ${options.from}`);
+
+    Promise
+      .all(values.map((value) => this._dappsStore._instanceReg.setMeta.estimateGas(options, value)))
+      .then((gas) => {
+        const newGas = gas.map((gas) => gas.mul(1.2));
+
+        gas.forEach((gas, index) => {
+          console.log('ModalStore:doUpdate', `${values[index][1]} gas estimated as ${gas.toFormat(0)}, setting to ${newGas[index].toFormat(0)}`);
+        });
+
+        const statusCallback = (error, status) => {
+          if (error) {
+          } else if (status.signerRequestId) {
+          } else if (status.transactionHash) {
+            this.setUpdateStep(3);
+          } else if (status.transactionReceipt) {
+            this.setUpdateStep(4);
+          }
+        };
+
+        return Promise.all(
+          newGas.map((gas, index) => {
+            return trackRequest(
+              this._dappsStore._instanceReg.setMeta.postTransaction(
+                Object.assign(options, { gas: gas.toFixed(0) }), values[index]
+              ), statusCallback
+            );
+          })
+        );
+      })
+      .then(() => {
+        this._dappsStore.refreshApp(appId);
+      })
+      .catch((error) => {
+        console.error('ModalStore:doUpdate', error);
+        this.setUpdateError(error);
+      });
+  }
+}
--- a/js/src/dapps/dappreg/parity.js
+++ b/js/src/dapps/dappreg/parity.js
@ -0,0 +1,53 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+const { api } = window.parity;
+
+function trackRequest (requestPromise, statusCallback) {
+  return requestPromise
+    .then((signerRequestId) => {
+      console.log('trackRequest', `posted to signer with requestId ${signerRequestId.toString()}`);
+      statusCallback(null, { signerRequestId });
+
+      return api.pollMethod('parity_checkRequest', signerRequestId);
+    })
+    .then((transactionHash) => {
+      console.log('trackRequest', `received transaction hash ${transactionHash}`);
+      statusCallback(null, { transactionHash });
+
+      return api.pollMethod('eth_getTransactionReceipt', transactionHash, (receipt) => {
+        if (!receipt || !receipt.blockNumber || receipt.blockNumber.eq(0)) {
+          return false;
+        }
+
+        return true;
+      });
+    })
+    .then((transactionReceipt) => {
+      console.log('trackRequest', 'received transaction receipt', transactionReceipt);
+      statusCallback(null, { transactionReceipt });
+    })
+    .catch((error) => {
+      console.error('trackRequest', error);
+      statusCallback(error);
+      throw error;
+    });
+}
+
+export {
+  api,
+  trackRequest
+};
--- a/js/src/index.js
+++ b/js/src/index.js
@ -46,6 +46,12 @@ import './index.html';

 injectTapEventPlugin();

+if (process.env.NODE_ENV === 'development') {
+  // Expose the React Performance Tools on the`window` object
+  const Perf = require('react-addons-perf');
+  window.Perf = Perf;
+}
+
 const AUTH_HASH = '#/auth?';
 const parityUrl = process.env.PARITY_URL ||
  (
--- a/js/src/modals/ExecuteContract/DetailsStep/detailsStep.js
+++ b/js/src/modals/ExecuteContract/DetailsStep/detailsStep.js
@ -36,6 +36,7 @@ export default class DetailsStep extends Component {
    onFuncChange: PropTypes.func,
    values: PropTypes.array.isRequired,
    valuesError: PropTypes.array.isRequired,
+    warning: PropTypes.string,
    onValueChange: PropTypes.func.isRequired
  }

@ -44,6 +45,7 @@ export default class DetailsStep extends Component {

    return (
      <Form>
+        { this.renderWarning() }
        <AddressSelect
          label='from account'
          hint='the account to transact with'
@ -178,6 +180,20 @@ export default class DetailsStep extends Component {
    });
  }

+  renderWarning () {
+    const { warning } = this.props;
+
+    if (!warning) {
+      return null;
+    }
+
+    return (
+      <div className={ styles.warning }>
+        { warning }
+      </div>
+    );
+  }
+
  onFuncChange = (event, index, signature) => {
    const { contract, onFuncChange } = this.props;

--- a/js/src/modals/ExecuteContract/executeContract.css
+++ b/js/src/modals/ExecuteContract/executeContract.css
@ -33,3 +33,12 @@
 .txhash {
  word-break: break-all;
 }
+
+.warning {
+  border-radius: 0.5em;
+  background: #f80;
+  color: white;
+  font-size: 0.75em;
+  padding: 0.75em;
+  text-align: center;
+}
--- a/js/src/modals/ExecuteContract/executeContract.js
+++ b/js/src/modals/ExecuteContract/executeContract.js
@ -15,17 +15,21 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.

 import React, { Component, PropTypes } from 'react';
+import { connect } from 'react-redux';
+import { bindActionCreators } from 'redux';
 import ActionDoneAll from 'material-ui/svg-icons/action/done-all';
 import ContentClear from 'material-ui/svg-icons/content/clear';

 import { BusyStep, CompletedStep, Button, IdentityIcon, Modal, TxHash } from '../../ui';
+import { MAX_GAS_ESTIMATION } from '../../util/constants';
 import { validateAddress, validateUint } from '../../util/validation';

 import DetailsStep from './DetailsStep';

+import ERRORS from '../Transfer/errors';
 import { ERROR_CODES } from '../../api/transport/error';

-export default class ExecuteContract extends Component {
+class ExecuteContract extends Component {
  static contextTypes = {
    api: PropTypes.object.isRequired,
    store: PropTypes.object.isRequired
@ -36,6 +40,7 @@ export default class ExecuteContract extends Component {
    fromAddress: PropTypes.string,
    accounts: PropTypes.object,
    contract: PropTypes.object,
+    gasLimit: PropTypes.object.isRequired,
    onClose: PropTypes.func.isRequired,
    onFromAddressChange: PropTypes.func.isRequired
  }
@ -46,6 +51,8 @@ export default class ExecuteContract extends Component {
    fromAddressError: null,
    func: null,
    funcError: null,
+    gas: null,
+    gasLimitError: null,
    values: [],
    valuesError: [],
    step: 0,
@ -64,6 +71,12 @@ export default class ExecuteContract extends Component {
    this.onFuncChange(null, functions[0]);
  }

+  componentWillReceiveProps (newProps) {
+    if (newProps.fromAddress !== this.props.fromAddress) {
+      this.estimateGas(newProps.fromAddress);
+    }
+  }
+
  render () {
    const { sending } = this.state;

@ -119,7 +132,7 @@ export default class ExecuteContract extends Component {

  renderStep () {
    const { onFromAddressChange } = this.props;
-    const { step, busyState, txhash, rejected } = this.state;
+    const { step, busyState, gasLimitError, txhash, rejected } = this.state;

    if (rejected) {
      return (
@ -135,6 +148,7 @@ export default class ExecuteContract extends Component {
        <DetailsStep
          { ...this.props }
          { ...this.state }
+          warning={ gasLimitError }
          onAmountChange={ this.onAmountChange }
          onFromAddressChange={ onFromAddressChange }
          onFuncChange={ this.onFuncChange }
@ -156,7 +170,7 @@ export default class ExecuteContract extends Component {
  }

  onAmountChange = (amount) => {
-    this.setState({ amount });
+    this.setState({ amount }, this.estimateGas);
  }

  onFuncChange = (event, func) => {
@ -182,7 +196,7 @@ export default class ExecuteContract extends Component {
    this.setState({
      func,
      values
-    });
+    }, this.estimateGas);
  }

  onValueChange = (event, index, _value) => {
@ -211,14 +225,55 @@ export default class ExecuteContract extends Component {
    this.setState({
      values: [].concat(values),
      valuesError: [].concat(valuesError)
+    }, () => {
+      if (!valueError) {
+        this.estimateGas();
+      }
    });
  }

+  estimateGas = (_fromAddress) => {
+    const { api } = this.context;
+    const { fromAddress, gasLimit } = this.props;
+    const { amount, func, values } = this.state;
+    const options = {
+      gas: MAX_GAS_ESTIMATION,
+      from: _fromAddress || fromAddress,
+      value: api.util.toWei(amount || 0)
+    };
+
+    if (!func) {
+      return;
+    }
+
+    func
+      .estimateGas(options, values)
+      .then((gasEst) => {
+        const gas = gasEst.mul(1.2);
+        let gasLimitError = null;
+
+        if (gas.gte(MAX_GAS_ESTIMATION)) {
+          gasLimitError = ERRORS.gasException;
+        } else if (gas.gt(gasLimit)) {
+          gasLimitError = ERRORS.gasBlockLimit;
+        }
+
+        this.setState({
+          gas,
+          gasLimitError
+        });
+      })
+      .catch((error) => {
+        console.warn('estimateGas', error);
+      });
+  }
+
  postTransaction = () => {
    const { api, store } = this.context;
    const { fromAddress } = this.props;
    const { amount, func, values } = this.state;
    const options = {
+      gas: MAX_GAS_ESTIMATION,
      from: fromAddress,
      value: api.util.toWei(amount || 0)
    };
@ -237,13 +292,13 @@ export default class ExecuteContract extends Component {

        return api
          .pollMethod('parity_checkRequest', requestId)
-          .catch((e) => {
-            if (e.code === ERROR_CODES.REQUEST_REJECTED) {
+          .catch((error) => {
+            if (error.code === ERROR_CODES.REQUEST_REJECTED) {
              this.setState({ rejected: true });
              return false;
            }

-            throw e;
+            throw error;
          });
      })
      .then((txhash) => {
@ -255,3 +310,18 @@ export default class ExecuteContract extends Component {
      });
  }
 }
+
+function mapStateToProps (state) {
+  const { gasLimit } = state.nodeStatus;
+
+  return { gasLimit };
+}
+
+function mapDispatchToProps (dispatch) {
+  return bindActionCreators({}, dispatch);
+}
+
+export default connect(
+  mapStateToProps,
+  mapDispatchToProps
+)(ExecuteContract);
--- a/js/src/modals/Shapeshift/shapeshift.js
+++ b/js/src/modals/Shapeshift/shapeshift.js
@ -63,6 +63,16 @@ export default class Shapeshift extends Component {
    this.retrieveCoins();
  }

+  componentWillUnmount () {
+    this.unsubscribe();
+  }
+
+  unsubscribe () {
+    // Unsubscribe from Shapeshit
+    const { depositAddress } = this.state;
+    shapeshift.unsubscribe(depositAddress);
+  }
+
  render () {
    const { error, stage } = this.state;

@ -205,6 +215,10 @@ export default class Shapeshift extends Component {
        console.log('onShift', result);
        const depositAddress = result.deposit;

+        if (this.state.depositAddress) {
+          this.unsubscribe();
+        }
+
        shapeshift.subscribe(depositAddress, this.onExchangeInfo);
        this.setState({ depositAddress });
      })
--- a/js/src/modals/Transfer/errors.js
+++ b/js/src/modals/Transfer/errors.js
@ -19,7 +19,9 @@ const ERRORS = {
  invalidAddress: 'the supplied address is an invalid network address',
  invalidAmount: 'the supplied amount should be a valid positive number',
  invalidDecimals: 'the supplied amount exceeds the allowed decimals',
-  largeAmount: 'the transaction total is higher than the available balance'
+  largeAmount: 'the transaction total is higher than the available balance',
+  gasException: 'the transaction will throw an exception with the current values',
+  gasBlockLimit: 'the transaction execution will exceed the block gas limit'
 };

 export default ERRORS;
--- a/js/src/modals/Transfer/transfer.css
+++ b/js/src/modals/Transfer/transfer.css
@ -14,6 +14,7 @@
 /* You should have received a copy of the GNU General Public License
 /* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 */
+
 .info {
  line-height: 1.618em;
  width: 100%;
@ -151,3 +152,13 @@
 .gasPriceDesc {
  font-size: 0.9em;
 }
+
+.warning {
+  border-radius: 0.5em;
+  background: #f80;
+  color: white;
+  font-size: 0.75em;
+  margin-bottom: 1em;
+  padding: 0.75em;
+  text-align: center;
+}
--- a/js/src/modals/Transfer/transfer.js
+++ b/js/src/modals/Transfer/transfer.js
@ -16,12 +16,15 @@

 import BigNumber from 'bignumber.js';
 import React, { Component, PropTypes } from 'react';
+import { connect } from 'react-redux';
+import { bindActionCreators } from 'redux';
 import ActionDoneAll from 'material-ui/svg-icons/action/done-all';
 import ContentClear from 'material-ui/svg-icons/content/clear';
 import NavigationArrowBack from 'material-ui/svg-icons/navigation/arrow-back';
 import NavigationArrowForward from 'material-ui/svg-icons/navigation/arrow-forward';

 import { BusyStep, CompletedStep, Button, IdentityIcon, Modal, TxHash } from '../../ui';
+import { DEFAULT_GAS, DEFAULT_GASPRICE, MAX_GAS_ESTIMATION } from '../../util/constants';

 import Details from './Details';
 import Extras from './Extras';
@ -30,8 +33,6 @@ import styles from './transfer.css';

 import { ERROR_CODES } from '../../api/transport/error';

-const DEFAULT_GAS = '21000';
-const DEFAULT_GASPRICE = '20000000000';
 const TITLES = {
  transfer: 'transfer details',
  sending: 'sending',
@ -42,7 +43,7 @@ const TITLES = {
 const STAGES_BASIC = [TITLES.transfer, TITLES.sending, TITLES.complete];
 const STAGES_EXTRA = [TITLES.transfer, TITLES.extras, TITLES.sending, TITLES.complete];

-export default class Transfer extends Component {
+class Transfer extends Component {
  static contextTypes = {
    api: PropTypes.object.isRequired,
    store: PropTypes.object.isRequired
@ -52,6 +53,7 @@ export default class Transfer extends Component {
    account: PropTypes.object,
    balance: PropTypes.object,
    balances: PropTypes.object,
+    gasLimit: PropTypes.object.isRequired,
    images: PropTypes.object.isRequired,
    onClose: PropTypes.func
  }
@ -64,6 +66,7 @@ export default class Transfer extends Component {
    gas: DEFAULT_GAS,
    gasEst: '0',
    gasError: null,
+    gasLimitError: null,
    gasPrice: DEFAULT_GASPRICE,
    gasPriceHistogram: {},
    gasPriceError: null,
@ -103,6 +106,7 @@ export default class Transfer extends Component {
        visible
        scroll
      >
+        { this.renderWarning() }
        { this.renderPage() }
      </Modal>
    );
@ -264,6 +268,20 @@ export default class Transfer extends Component {
    }
  }

+  renderWarning () {
+    const { gasLimitError } = this.state;
+
+    if (!gasLimitError) {
+      return null;
+    }
+
+    return (
+      <div className={ styles.warning }>
+        { gasLimitError }
+      </div>
+    );
+  }
+
  isValid () {
    const detailsValid = !this.state.recipientError && !this.state.valueError && !this.state.totalError;
    const extrasValid = !this.state.gasError && !this.state.gasPriceError && !this.state.totalError;
@ -519,6 +537,7 @@ export default class Transfer extends Component {

    return token.contract.instance.transfer
      .estimateGas({
+        gas: MAX_GAS_ESTIMATION,
        from: account.address,
        to: token.address
      }, [
@ -532,6 +551,7 @@ export default class Transfer extends Component {
    const { account } = this.props;
    const { data, recipient, value } = this.state;
    const options = {
+      gas: MAX_GAS_ESTIMATION,
      from: account.address,
      to: recipient,
      value: api.util.toWei(value || 0)
@ -552,19 +572,29 @@ export default class Transfer extends Component {
      return;
    }

+    const { gasLimit } = this.props;
+
    (this.state.isEth
      ? this._estimateGasEth()
      : this._estimateGasToken()
-    ).then((_value) => {
-      let gas = _value;
+    ).then((gasEst) => {
+      let gas = gasEst;
+      let gasLimitError = null;

      if (gas.gt(DEFAULT_GAS)) {
        gas = gas.mul(1.2);
      }

+      if (gas.gte(MAX_GAS_ESTIMATION)) {
+        gasLimitError = ERRORS.gasException;
+      } else if (gas.gt(gasLimit)) {
+        gasLimitError = ERRORS.gasBlockLimit;
+      }
+
      this.setState({
        gas: gas.toFixed(0),
-        gasEst: _value.toFormat()
+        gasEst: gasEst.toFormat(),
+        gasLimitError
      }, this.recalculate);
    })
    .catch((error) => {
@ -649,3 +679,18 @@ export default class Transfer extends Component {
    store.dispatch({ type: 'newError', error });
  }
 }
+
+function mapStateToProps (state) {
+  const { gasLimit } = state.nodeStatus;
+
+  return { gasLimit };
+}
+
+function mapDispatchToProps (dispatch) {
+  return bindActionCreators({}, dispatch);
+}
+
+export default connect(
+  mapStateToProps,
+  mapDispatchToProps
+)(Transfer);
--- a/js/src/redux/providers/balances.js
+++ b/js/src/redux/providers/balances.js
@ -31,13 +31,23 @@ export default class Balances {
  constructor (store, api) {
    this._api = api;
    this._store = store;
+
+    this._tokens = {};
+    this._images = {};
+
    this._accountsInfo = null;
-    this._tokens = [];
+    this._tokenreg = null;
+    this._fetchingTokens = false;
+    this._fetchedTokens = false;
+
+    this._tokenregSubId = null;
+    this._tokenregMetaSubId = null;
  }

  start () {
    this._subscribeBlockNumber();
    this._subscribeAccountsInfo();
+    this._retrieveTokens();
  }

  _subscribeAccountsInfo () {
@ -48,10 +58,7 @@ export default class Balances {
        }

        this._accountsInfo = accountsInfo;
-        this._retrieveBalances();
-      })
-      .then((subscriptionId) => {
-        console.log('_subscribeAccountsInfo', 'subscriptionId', subscriptionId);
+        this._retrieveTokens();
      })
      .catch((error) => {
        console.warn('_subscribeAccountsInfo', error);
@ -62,21 +69,22 @@ export default class Balances {
    this._api
      .subscribe('eth_blockNumber', (error) => {
        if (error) {
-          return;
+          return console.warn('_subscribeBlockNumber', error);
        }

        this._retrieveTokens();
      })
-      .then((subscriptionId) => {
-        console.log('_subscribeBlockNumber', 'subscriptionId', subscriptionId);
-      })
      .catch((error) => {
        console.warn('_subscribeBlockNumber', error);
      });
  }

-  _retrieveTokens () {
-    this._api.parity
+  getTokenRegistry () {
+    if (this._tokenreg) {
+      return Promise.resolve(this._tokenreg);
+    }
+
+    return this._api.parity
      .registryAddress()
      .then((registryAddress) => {
        const registry = this._api.newContract(abis.registry, registryAddress);
@ -85,60 +93,49 @@ export default class Balances {
      })
      .then((tokenregAddress) => {
        const tokenreg = this._api.newContract(abis.tokenreg, tokenregAddress);
+        this._tokenreg = tokenreg;
+        this.attachToTokens();

+        return tokenreg;
+      });
+  }
+
+  _retrieveTokens () {
+    if (this._fetchingTokens) {
+      return;
+    }
+
+    if (this._fetchedTokens) {
+      return this._retrieveBalances();
+    }
+
+    this._fetchingTokens = true;
+    this._fetchedTokens = false;
+
+    this
+      .getTokenRegistry()
+      .then((tokenreg) => {
        return tokenreg.instance.tokenCount
          .call()
          .then((numTokens) => {
-            const promisesTokens = [];
-            const promisesImages = [];
+            const promises = [];

-            while (promisesTokens.length < numTokens.toNumber()) {
-              const index = promisesTokens.length;
-
-              promisesTokens.push(tokenreg.instance.token.call({}, [index]));
-              promisesImages.push(tokenreg.instance.meta.call({}, [index, 'IMG']));
+            for (let i = 0; i < numTokens.toNumber(); i++) {
+              promises.push(this.fetchTokenInfo(tokenreg, i));
            }

-            return Promise.all([
-              Promise.all(promisesTokens),
-              Promise.all(promisesImages)
-            ]);
+            return Promise.all(promises);
          });
      })
-      .then(([_tokens, images]) => {
-        const tokens = {};
-        this._tokens = _tokens
-          .map((_token, index) => {
-            const [address, tag, format, name] = _token;
+      .then(() => {
+        this._fetchingTokens = false;
+        this._fetchedTokens = true;

-            const token = {
-              address,
-              name,
-              tag,
-              format: format.toString(),
-              contract: this._api.newContract(abis.eip20, address)
-            };
-            tokens[address] = token;
-            this._store.dispatch(setAddressImage(address, images[index]));
-
-            return token;
-          })
-          .sort((a, b) => {
-            if (a.tag < b.tag) {
-              return -1;
-            } else if (a.tag > b.tag) {
-              return 1;
-            }
-
-            return 0;
-          });
-
-        this._store.dispatch(getTokens(tokens));
+        this._store.dispatch(getTokens(this._tokens));
        this._retrieveBalances();
      })
      .catch((error) => {
-        console.warn('_retrieveTokens', error);
-        this._retrieveBalances();
+        console.warn('balances::_retrieveTokens', error);
      });
  }

@ -147,48 +144,20 @@ export default class Balances {
      return;
    }

-    const addresses = Object.keys(this._accountsInfo);
+    const addresses = Object
+      .keys(this._accountsInfo)
+      .filter((address) => {
+        const account = this._accountsInfo[address];
+        return !account.meta || !account.meta.deleted;
+      });
+
    this._balances = {};

    Promise
-      .all(
-        addresses.map((address) => Promise.all([
-          this._api.eth.getBalance(address),
-          this._api.eth.getTransactionCount(address)
-        ]))
-      )
-      .then((balanceTxCount) => {
-        return Promise.all(
-          balanceTxCount.map(([value, txCount], idx) => {
-            const address = addresses[idx];
-
-            this._balances[address] = {
-              txCount,
-              tokens: [{
-                token: ETH,
-                value
-              }]
-            };
-
-            return Promise.all(
-              this._tokens.map((token) => {
-                return token.contract.instance.balanceOf.call({}, [address]);
-              })
-            );
-          })
-        );
-      })
-      .then((tokenBalances) => {
-        addresses.forEach((address, idx) => {
-          const balanceOf = tokenBalances[idx];
-          const balance = this._balances[address];
-
-          this._tokens.forEach((token, tidx) => {
-            balance.tokens.push({
-              token,
-              value: balanceOf[tidx]
-            });
-          });
+      .all(addresses.map((a) => this.fetchAccountBalance(a)))
+      .then((balances) => {
+        addresses.forEach((a, idx) => {
+          this._balances[a] = balances[idx];
        });

        this._store.dispatch(getBalances(this._balances));
@ -197,4 +166,161 @@ export default class Balances {
        console.warn('_retrieveBalances', error);
      });
  }
+
+  attachToTokens () {
+    this.attachToTokenMetaChange();
+    this.attachToNewToken();
+  }
+
+  attachToNewToken () {
+    if (this._tokenregSubId) {
+      return;
+    }
+
+    this._tokenreg
+      .instance
+      .Registered
+      .subscribe({
+        fromBlock: 0,
+        toBlock: 'latest',
+        skipInitFetch: true
+      }, (error, logs) => {
+        if (error) {
+          return console.error('balances::attachToNewToken', 'failed to attach to tokenreg Registered', error.toString(), error.stack);
+        }
+
+        const promises = logs.map((log) => {
+          const id = log.params.id.value.toNumber();
+          return this.fetchTokenInfo(this._tokenreg, id);
+        });
+
+        return Promise.all(promises);
+      })
+      .then((tokenregSubId) => {
+        this._tokenregSubId = tokenregSubId;
+      })
+      .catch((e) => {
+        console.warn('balances::attachToNewToken', e);
+      });
+  }
+
+  attachToTokenMetaChange () {
+    if (this._tokenregMetaSubId) {
+      return;
+    }
+
+    this._tokenreg
+      .instance
+      .MetaChanged
+      .subscribe({
+        fromBlock: 0,
+        toBlock: 'latest',
+        topics: [ null, this._api.util.asciiToHex('IMG') ],
+        skipInitFetch: true
+      }, (error, logs) => {
+        if (error) {
+          return console.error('balances::attachToTokenMetaChange', 'failed to attach to tokenreg MetaChanged', error.toString(), error.stack);
+        }
+
+        // In case multiple logs for same token
+        // in one block. Take the last value.
+        const tokens = logs
+          .filter((log) => log.type === 'mined')
+          .reduce((_tokens, log) => {
+            const id = log.params.id.value.toNumber();
+            const image = log.params.value.value;
+
+            const token = Object.values(this._tokens).find((c) => c.id === id);
+            const { address } = token;
+
+            _tokens[address] = { address, id, image };
+            return _tokens;
+          }, {});
+
+        Object
+          .values(tokens)
+          .forEach((token) => {
+            const { address, image } = token;
+
+            if (this._images[address] !== image.toString()) {
+              this._store.dispatch(setAddressImage(address, image));
+              this._images[address] = image.toString();
+            }
+          });
+      })
+      .then((tokenregMetaSubId) => {
+        this._tokenregMetaSubId = tokenregMetaSubId;
+      })
+      .catch((e) => {
+        console.warn('balances::attachToTokenMetaChange', e);
+      });
+  }
+
+  fetchTokenInfo (tokenreg, tokenId) {
+    return Promise
+      .all([
+        tokenreg.instance.token.call({}, [tokenId]),
+        tokenreg.instance.meta.call({}, [tokenId, 'IMG'])
+      ])
+      .then(([ tokenData, image ]) => {
+        const [ address, tag, format, name ] = tokenData;
+        const contract = this._api.newContract(abis.eip20, address);
+
+        if (this._images[address] !== image.toString()) {
+          this._store.dispatch(setAddressImage(address, image));
+          this._images[address] = image.toString();
+        }
+
+        const token = {
+          format: format.toString(),
+          id: tokenId,
+
+          address,
+          tag,
+          name,
+          contract
+        };
+
+        this._tokens[address] = token;
+
+        return token;
+      })
+      .catch((e) => {
+        console.warn('balances::fetchTokenInfo', `couldn't fetch token #${tokenId}`, e);
+      });
+  }
+
+  /**
+   * TODO?: txCount is only shown on an address page, so we
+   * might not need to fetch it for each address for each block,
+   * but only for one address when the user is on the account
+   * view.
+   */
+  fetchAccountBalance (address) {
+    const _tokens = Object.values(this._tokens);
+    const tokensPromises = _tokens
+      .map((token) => {
+        return token.contract.instance.balanceOf.call({}, [ address ]);
+      });
+
+    return Promise
+      .all([
+        this._api.eth.getTransactionCount(address),
+        this._api.eth.getBalance(address)
+      ].concat(tokensPromises))
+      .then(([ txCount, ethBalance, ...tokensBalance ]) => {
+        const tokens = []
+          .concat(
+            { token: ETH, value: ethBalance },
+            _tokens
+              .map((token, index) => ({
+                token,
+                value: tokensBalance[index]
+              }))
+          );
+
+        const balance = { txCount, tokens };
+        return balance;
+      });
+  }
 }
--- a/js/src/ui/ParityBackground/parityBackground.js
+++ b/js/src/ui/ParityBackground/parityBackground.js
@ -16,26 +16,17 @@

 import React, { Component, PropTypes } from 'react';
 import { connect } from 'react-redux';
-import { bindActionCreators } from 'redux';

 class ParityBackground extends Component {
-  static contextTypes = {
-    muiTheme: PropTypes.object.isRequired
-  }
-
  static propTypes = {
+    style: PropTypes.object.isRequired,
    children: PropTypes.node,
    className: PropTypes.string,
-    gradient: PropTypes.string,
-    seed: PropTypes.any,
-    settings: PropTypes.object.isRequired,
    onClick: PropTypes.func
-  }
+  };

  render () {
-    const { muiTheme } = this.context;
-    const { children, className, gradient, seed, settings, onClick } = this.props;
-    const style = muiTheme.parity.getBackgroundStyle(gradient, seed || settings.backgroundSeed);
+    const { children, className, style, onClick } = this.props;

    return (
      <div
@ -48,17 +39,29 @@ class ParityBackground extends Component {
  }
 }

-function mapStateToProps (state) {
-  const { settings } = state;
+function mapStateToProps (_, initProps) {
+  const { gradient, seed, muiTheme } = initProps;

-  return { settings };
-}
+  let _seed = seed;
+  let _props = { style: muiTheme.parity.getBackgroundStyle(gradient, seed) };

-function mapDispatchToProps (dispatch) {
-  return bindActionCreators({}, dispatch);
+  return (state, props) => {
+    const { backgroundSeed } = state.settings;
+    const { seed } = props;
+
+    const newSeed = seed || backgroundSeed;
+
+    if (newSeed === _seed) {
+      return _props;
+    }
+
+    _seed = newSeed;
+    _props = { style: muiTheme.parity.getBackgroundStyle(gradient, newSeed) };
+
+    return _props;
+  };
 }

 export default connect(
-  mapStateToProps,
-  mapDispatchToProps
+  mapStateToProps
 )(ParityBackground);
--- a/js/src/util/constants.js
+++ b/js/src/util/constants.js
@ -0,0 +1,26 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+const DEFAULT_GAS = '21000';
+const DEFAULT_GASPRICE = '20000000000';
+
+const MAX_GAS_ESTIMATION = '50000000';
+
+export {
+  DEFAULT_GAS,
+  DEFAULT_GASPRICE,
+  MAX_GAS_ESTIMATION
+};
--- a/js/src/views/Accounts/Summary/summary.js
+++ b/js/src/views/Accounts/Summary/summary.js
@ -16,6 +16,7 @@

 import React, { Component, PropTypes } from 'react';
 import { Link } from 'react-router';
+import { isEqual } from 'lodash';

 import { Balance, Container, ContainerTitle, IdentityIcon, IdentityName, Tags, Input } from '../../../ui';

@ -30,7 +31,6 @@ export default class Summary extends Component {
    link: PropTypes.string,
    name: PropTypes.string,
    noLink: PropTypes.bool,
-    children: PropTypes.node,
    handleAddSearchToken: PropTypes.func
  };

@ -42,8 +42,42 @@ export default class Summary extends Component {
    name: 'Unnamed'
  };

+  shouldComponentUpdate (nextProps) {
+    const prev = {
+      link: this.props.link, name: this.props.name,
+      noLink: this.props.noLink,
+      meta: this.props.account.meta, address: this.props.account.address
+    };
+
+    const next = {
+      link: nextProps.link, name: nextProps.name,
+      noLink: nextProps.noLink,
+      meta: nextProps.account.meta, address: nextProps.account.address
+    };
+
+    if (!isEqual(next, prev)) {
+      return true;
+    }
+
+    const prevTokens = this.props.balance.tokens || [];
+    const nextTokens = nextProps.balance.tokens || [];
+
+    if (prevTokens.length !== nextTokens.length) {
+      return true;
+    }
+
+    const prevValues = prevTokens.map((t) => t.value.toNumber());
+    const nextValues = nextTokens.map((t) => t.value.toNumber());
+
+    if (!isEqual(prevValues, nextValues)) {
+      return true;
+    }
+
+    return false;
+  }
+
  render () {
-    const { account, children, handleAddSearchToken } = this.props;
+    const { account, handleAddSearchToken } = this.props;
    const { tags } = account.meta;

    if (!account) {
@ -71,7 +105,6 @@ export default class Summary extends Component {
          byline={ addressComponent } />

        { this.renderBalance() }
-        { children }
      </Container>
    );
  }
--- a/js/src/views/Accounts/accounts.css
+++ b/js/src/views/Accounts/accounts.css
@ -30,3 +30,25 @@
  right: 1em;
  top: 4em;
 }
+
+.loadings {
+  display: flex;
+  flex-wrap: wrap;
+
+  .loading {
+    flex: 0 1 50%;
+    width: 50%;
+    height: 150px;
+    display: flex;
+    padding: 0.25em;
+    box-sizing: border-box;
+
+    > div {
+      display: flex;
+      flex: 1;
+      align-items: center;
+      justify-content: center;
+      background-color: rgba(0, 0, 0, 0.8);
+    }
+  }
+}
--- a/js/src/views/Accounts/accounts.js
+++ b/js/src/views/Accounts/accounts.js
@ -42,33 +42,63 @@ class Accounts extends Component {
    newDialog: false,
    sortOrder: '',
    searchValues: [],
-    searchTokens: []
+    searchTokens: [],
+    show: false
+  }
+
+  componentWillMount () {
+    window.setTimeout(() => {
+      this.setState({ show: true });
+    }, 100);
  }

  render () {
-    const { accounts, hasAccounts, balances } = this.props;
-    const { searchValues, sortOrder } = this.state;
-
    return (
      <div className={ styles.accounts }>
        { this.renderNewDialog() }
        { this.renderActionbar() }
-        <Page>
-          <List
-            search={ searchValues }
-            accounts={ accounts }
-            balances={ balances }
-            empty={ !hasAccounts }
-            order={ sortOrder }
-            handleAddSearchToken={ this.onAddSearchToken } />
-          <Tooltip
-            className={ styles.accountTooltip }
-            text='your accounts are visible for easy access, allowing you to edit the meta information, make transfers, view transactions and fund the account' />
-        </Page>
+
+        { this.state.show ? this.renderAccounts() : this.renderLoading() }
      </div>
    );
  }

+  renderLoading () {
+    const { accounts } = this.props;
+
+    const loadings = ((accounts && Object.keys(accounts)) || []).map((_, idx) => (
+      <div key={ idx } className={ styles.loading }>
+        <div></div>
+      </div>
+    ));
+
+    return (
+      <div className={ styles.loadings }>
+        { loadings }
+      </div>
+    );
+  }
+
+  renderAccounts () {
+    const { accounts, hasAccounts, balances } = this.props;
+    const { searchValues, sortOrder } = this.state;
+
+    return (
+      <Page>
+        <List
+          search={ searchValues }
+          accounts={ accounts }
+          balances={ balances }
+          empty={ !hasAccounts }
+          order={ sortOrder }
+          handleAddSearchToken={ this.onAddSearchToken } />
+        <Tooltip
+          className={ styles.accountTooltip }
+          text='your accounts are visible for easy access, allowing you to edit the meta information, make transfers, view transactions and fund the account' />
+      </Page>
+    );
+  }
+
  renderSearchButton () {
    const onChange = (searchTokens, searchValues) => {
      this.setState({ searchTokens, searchValues });
--- a/js/src/views/Application/Container/container.js
+++ b/js/src/views/Application/Container/container.js
@ -22,6 +22,10 @@ import { Errors, ParityBackground, Tooltips } from '../../../ui';
 import styles from '../application.css';

 export default class Container extends Component {
+  static contextTypes = {
+    muiTheme: PropTypes.object.isRequired
+  };
+
  static propTypes = {
    children: PropTypes.node.isRequired,
    showFirstRun: PropTypes.bool,
@ -30,9 +34,10 @@ export default class Container extends Component {

  render () {
    const { children, showFirstRun, onCloseFirstRun } = this.props;
+    const { muiTheme } = this.context;

    return (
-      <ParityBackground className={ styles.container }>
+      <ParityBackground className={ styles.container } muiTheme={ muiTheme }>
        <FirstRun
          visible={ showFirstRun }
          onClose={ onCloseFirstRun } />
--- a/js/src/views/Application/TabBar/tabBar.css
+++ b/js/src/views/Application/TabBar/tabBar.css
@ -23,6 +23,11 @@
 .tabs {
  width: 100%;
  position: relative;
+  display: flex;
+
+  & > * {
+    flex: 1;
+  }
 }

 .tabs button,
@ -38,6 +43,7 @@

 button.tabactive,
 button.tabactive:hover {
+  color: white !important;
  background: rgba(0, 0, 0, 0.25) !important;
  border-radius: 4px 4px 0 0;
 }
--- a/js/src/views/Application/TabBar/tabBar.js
+++ b/js/src/views/Application/TabBar/tabBar.js
@ -18,7 +18,7 @@ import React, { Component, PropTypes } from 'react';
 import { connect } from 'react-redux';
 import { bindActionCreators } from 'redux';
 import { Toolbar, ToolbarGroup } from 'material-ui/Toolbar';
-import { Tabs, Tab } from 'material-ui/Tabs';
+import { Tab as MUITab } from 'material-ui/Tabs';

 import { Badge, Tooltip } from '../../../ui';

@ -33,20 +33,138 @@ const TABMAP = {
  deploy: 'contract'
 };

+class Tab extends Component {
+  static propTypes = {
+    active: PropTypes.bool,
+    view: PropTypes.object,
+    children: PropTypes.node,
+    pendings: PropTypes.number,
+    onChange: PropTypes.func
+  };
+
+  shouldComponentUpdate (nextProps) {
+    return nextProps.active !== this.props.active ||
+      (nextProps.view.id === 'signer' && nextProps.pendings !== this.props.pendings);
+  }
+
+  render () {
+    const { active, view, children } = this.props;
+
+    const label = this.getLabel(view);
+
+    return (
+      <MUITab
+        className={ active ? styles.tabactive : '' }
+        selected={ active }
+        icon={ view.icon }
+        label={ label }
+        onClick={ this.handleClick }
+      >
+        { children }
+      </MUITab>
+    );
+  }
+
+  getLabel (view) {
+    const { label } = view;
+
+    if (view.id === 'signer') {
+      return this.renderSignerLabel(label);
+    }
+
+    if (view.id === 'status') {
+      return this.renderStatusLabel(label);
+    }
+
+    return this.renderLabel(label);
+  }
+
+  renderLabel (name, bubble) {
+    return (
+      <div className={ styles.label }>
+        { name }
+        { bubble }
+      </div>
+    );
+  }
+
+  renderSignerLabel (label) {
+    const { pendings } = this.props;
+
+    if (pendings) {
+      const bubble = (
+        <Badge
+          color='red'
+          className={ styles.labelBubble }
+          value={ pendings } />
+      );
+
+      return this.renderLabel(label, bubble);
+    }
+
+    return this.renderLabel(label);
+  }
+
+  renderStatusLabel (label) {
+    // const { isTest, netChain } = this.props;
+    // const bubble = (
+    //   <Badge
+    //     color={ isTest ? 'red' : 'default' }
+    //     className={ styles.labelBubble }
+    //     value={ isTest ? 'TEST' : netChain } />
+    //   );
+
+    return this.renderLabel(label, null);
+  }
+
+  handleClick = () => {
+    const { onChange, view } = this.props;
+    onChange(view);
+  }
+}
+
 class TabBar extends Component {
  static contextTypes = {
    router: PropTypes.object.isRequired
-  }
+  };

  static propTypes = {
+    views: PropTypes.array.isRequired,
+    hash: PropTypes.string.isRequired,
    pending: PropTypes.array,
    isTest: PropTypes.bool,
-    netChain: PropTypes.string,
-    settings: PropTypes.object.isRequired
-  }
+    netChain: PropTypes.string
+  };
+
+  static defaultProps = {
+    pending: []
+  };

  state = {
-    activeRoute: '/accounts'
+    activeViewId: ''
+  };
+
+  setActiveView (props = this.props) {
+    const { hash, views } = props;
+    const view = views.find((view) => view.value === hash);
+
+    this.setState({ activeViewId: view.id });
+  }
+
+  componentWillMount () {
+    this.setActiveView();
+  }
+
+  componentWillReceiveProps (nextProps) {
+    if (nextProps.hash !== this.props.hash) {
+      this.setActiveView(nextProps);
+    }
+  }
+
+  shouldComponentUpdate (nextProps, nextState) {
+    return (nextProps.hash !== this.props.hash) ||
+      (nextProps.pending.length !== this.props.pending.length) ||
+      (nextState.activeViewId !== this.state.activeViewId);
  }

  render () {
@ -81,100 +199,64 @@ class TabBar extends Component {
  }

  renderTabs () {
-    const { settings } = this.props;
-    const windowHash = (window.location.hash || '').split('?')[0].split('/')[1];
-    const hash = TABMAP[windowHash] || windowHash;
+    const { views, pending } = this.props;
+    const { activeViewId } = this.state;

-    const items = Object.keys(settings.views)
-      .filter((id) => settings.views[id].fixed || settings.views[id].active)
-      .map((id) => {
-        const view = settings.views[id];
-        let label = this.renderLabel(view.label);
-        let body = null;
+    const items = views
+      .map((view, index) => {
+        const body = (view.id === 'accounts')
+          ? (
+          <Tooltip className={ styles.tabbarTooltip } text='navigate between the different parts and views of the application, switching between an account view, token view and distributed application view' />
+          )
+          : null;

-        if (id === 'accounts') {
-          body = (
-            <Tooltip className={ styles.tabbarTooltip } text='navigate between the different parts and views of the application, switching between an account view, token view and distributed application view' />
-          );
-        } else if (id === 'signer') {
-          label = this.renderSignerLabel(label);
-        } else if (id === 'status') {
-          label = this.renderStatusLabel(label);
-        }
+        const active = activeViewId === view.id;

        return (
          <Tab
-            className={ hash === view.value ? styles.tabactive : '' }
-            value={ view.value }
-            icon={ view.icon }
-            key={ id }
-            label={ label }
-            onActive={ this.onActivate(view.route) }>
+            active={ active }
+            view={ view }
+            onChange={ this.onChange }
+            key={ index }
+            pendings={ pending.length }
+          >
            { body }
          </Tab>
        );
      });

    return (
-      <Tabs
+      <div
        className={ styles.tabs }
-        value={ hash }>
+        onChange={ this.onChange }>
        { items }
-      </Tabs>
-    );
-  }
-
-  renderLabel = (name, bubble) => {
-    return (
-      <div className={ styles.label }>
-        { name }
-        { bubble }
      </div>
    );
  }

-  renderSignerLabel = (label) => {
-    const { pending } = this.props;
-    let bubble = null;
-
-    if (pending && pending.length) {
-      bubble = (
-        <Badge
-          color='red'
-          className={ styles.labelBubble }
-          value={ pending.length } />
-      );
-    }
-
-    return this.renderLabel(label, bubble);
-  }
-
-  renderStatusLabel = (label) => {
-    // const { isTest, netChain } = this.props;
-    // const bubble = (
-    //   <Badge
-    //     color={ isTest ? 'red' : 'default' }
-    //     className={ styles.labelBubble }
-    //     value={ isTest ? 'TEST' : netChain } />
-    //   );
-
-    return this.renderLabel(label, null);
-  }
-
-  onActivate = (activeRoute) => {
+  onChange = (view) => {
    const { router } = this.context;

-    return (event) => {
-      router.push(activeRoute);
-      this.setState({ activeRoute });
-    };
+    router.push(view.route);
+    this.setState({ activeViewId: view.id });
  }
 }

 function mapStateToProps (state) {
-  const { settings } = state;
+  const { views } = state.settings;

-  return { settings };
+  const filteredViews = Object
+    .keys(views)
+    .filter((id) => views[id].fixed || views[id].active)
+    .map((id) => ({
+      ...views[id],
+      id
+    }));
+
+  const windowHash = (window.location.hash || '').split('?')[0].split('/')[1];
+  const hash = TABMAP[windowHash] || windowHash;
+
+  return { views: filteredViews, hash };
 }

 function mapDispatchToProps (dispatch) {
--- a/js/src/views/Dapps/builtin.json
+++ b/js/src/views/Dapps/builtin.json
@ -52,6 +52,7 @@
    "description": "Have a peak on internals of transaction queue of your node.",
    "author": "Parity Team <admin@ethcore.io>",
    "version": "1.0.0",
+    "visible": true,
    "secure": true
  }
 ]
--- a/js/src/views/ParityBar/parityBar.js
+++ b/js/src/views/ParityBar/parityBar.js
@ -28,6 +28,10 @@ import imagesEthcoreBlock from '../../../assets/images/parity-logo-white-no-text
 import styles from './parityBar.css';

 class ParityBar extends Component {
+  static contextTypes = {
+    muiTheme: PropTypes.object.isRequired
+  };
+
  static propTypes = {
    pending: PropTypes.array,
    dapp: PropTypes.bool
@ -62,6 +66,7 @@ class ParityBar extends Component {

  renderBar () {
    const { dapp } = this.props;
+    const { muiTheme } = this.context;

    if (!dapp) {
      return null;
@ -75,7 +80,7 @@ class ParityBar extends Component {

    return (
      <div className={ styles.bar }>
-        <ParityBackground className={ styles.corner }>
+        <ParityBackground className={ styles.corner } muiTheme={ muiTheme }>
          <div className={ styles.cornercolor }>
            <Link to='/apps'>
              <Button
@ -95,9 +100,11 @@ class ParityBar extends Component {
  }

  renderExpanded () {
+    const { muiTheme } = this.context;
+
    return (
      <div className={ styles.overlay }>
-        <ParityBackground className={ styles.expanded }>
+        <ParityBackground className={ styles.expanded } muiTheme={ muiTheme }>
          <div className={ styles.header }>
            <div className={ styles.title }>
              <ContainerTitle title='Parity Signer: Pending' />
--- a/js/src/views/Settings/Background/background.js
+++ b/js/src/views/Settings/Background/background.js
@ -81,6 +81,7 @@ class Background extends Component {
  renderBackgrounds () {
    const { settings } = this.props;
    const { seeds } = this.state;
+    const { muiTheme } = this.context;

    return seeds.map((seed, index) => {
      return (
@ -89,7 +90,9 @@ class Background extends Component {
            <ParityBackground
              className={ settings.backgroundSeed === seed ? styles.seedactive : styles.seed }
              seed={ seed }
-              onClick={ this.onSelect(seed) } />
+              onClick={ this.onSelect(seed) }
+              muiTheme={ muiTheme }
+            />
          </div>
        </div>
      );
--- a/js/test/mockRpc.js
+++ b/js/test/mockRpc.js
@ -23,9 +23,10 @@ export const TEST_HTTP_URL = 'http://localhost:6688';
 export const TEST_WS_URL = 'ws://localhost:8866';

 export function mockHttp (requests) {
+  nock.cleanAll();
  let scope = nock(TEST_HTTP_URL);

-  requests.forEach((request) => {
+  requests.forEach((request, index) => {
    scope = scope
      .post('/')
      .reply(request.code || 200, (uri, body) => {
--- a/js/webpack.config.js
+++ b/js/webpack.config.js
@ -37,6 +37,7 @@ module.exports = {
  entry: {
    // dapps
    'basiccoin': ['./dapps/basiccoin.js'],
+    'dappreg': ['./dapps/dappreg.js'],
    'githubhint': ['./dapps/githubhint.js'],
    'registry': ['./dapps/registry.js'],
    'signaturereg': ['./dapps/signaturereg.js'],