diff --git a/Libraries/WebSocket/RCTWebSocketExecutor.m b/Libraries/WebSocket/RCTWebSocketExecutor.m
index 2ee409f33..de26e8a91 100644
--- a/Libraries/WebSocket/RCTWebSocketExecutor.m
+++ b/Libraries/WebSocket/RCTWebSocketExecutor.m
@@ -51,7 +51,7 @@ RCT_EXPORT_MODULE()
   if (!_url) {
     NSUserDefaults *standardDefaults = [NSUserDefaults standardUserDefaults];
     NSInteger port = [standardDefaults integerForKey:@"websocket-executor-port"] ?: 8081;
-    NSString *URLString = [NSString stringWithFormat:@"http://localhost:%zd/debugger-proxy", port];
+    NSString *URLString = [NSString stringWithFormat:@"http://localhost:%zd/debugger-proxy?role=client", port];
     _url = [RCTConvert NSURL:URLString];
   }
 
diff --git a/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevServerHelper.java b/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevServerHelper.java
index 515cab3a5..79a71b242 100644
--- a/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevServerHelper.java
+++ b/ReactAndroid/src/main/java/com/facebook/react/devsupport/DevServerHelper.java
@@ -62,7 +62,7 @@ public class DevServerHelper {
       "http://%s/launch-chrome-devtools";
   private static final String ONCHANGE_ENDPOINT_URL_FORMAT =
       "http://%s/onchange";
-  private static final String WEBSOCKET_PROXY_URL_FORMAT = "ws://%s/debugger-proxy";
+  private static final String WEBSOCKET_PROXY_URL_FORMAT = "ws://%s/debugger-proxy?role=client";
   private static final String PACKAGER_STATUS_URL_FORMAT = "http://%s/status";
 
   private static final String PACKAGER_OK_STATUS = "packager-status:running";
diff --git a/local-cli/server/util/debugger.html b/local-cli/server/util/debugger.html
index 3d1c5947e..878574260 100644
--- a/local-cli/server/util/debugger.html
+++ b/local-cli/server/util/debugger.html
@@ -17,83 +17,82 @@
 <script>
 (function() {
 
-var sessionID = window.localStorage.getItem('sessionID');
-window.localStorage.removeItem('sessionID');
-
-window.onbeforeunload = function() {
-  if (sessionID) {
-    return 'If you reload this page, it is going to break the debugging session. ' +
-      'You should press ⌘R in simulator to reload.';
-  }
-};
-
-// Alias native implementations needed by the debugger before platform-specific
-// implementations are loaded into the global namespace
-var debuggerSetTimeout = window.setTimeout;
-var DebuggerWebSocket = window.WebSocket;
-
 function setStatus(status) {
   document.getElementById('status').innerHTML = status;
 }
 
-// This worker will run the application javascript code,
-// making sure that it's run in an environment without a global
-// document, to make it consistent with the JSC executor environment.
-var worker = new Worker('debuggerWorker.js');
-
-var messageHandlers = {
-  // This method is a bit hacky. Catalyst asks for a new clean JS runtime.
-  // The easiest way to do this is to reload this page. That also means that
-  // web socket connection will be lost. To send reply back we need to remember
-  // message id.
-  // This message also needs to be handled outside of the worker, since the worker
-  // doesn't have access to local storage.
-  'prepareJSRuntime': function(message) {
-    window.onbeforeunload = undefined;
-    window.localStorage.setItem('sessionID', message.id);
-    window.location.reload();
-  }
-};
+var INITIAL_MESSAGE = 'Waiting, press <span class="shortcut">⌘R</span> in simulator to reload and connect.';
 
 function connectToDebuggerProxy() {
-  var ws = new DebuggerWebSocket('ws://' + window.location.host + '/debugger-proxy');
+  var worker;
+  var ws = new WebSocket('ws://' + window.location.host + '/debugger-proxy?role=debugger&name=Chrome');
+
+  function createJSRuntime() {
+    // This worker will run the application javascript code,
+    // making sure that it's run in an environment without a global
+    // document, to make it consistent with the JSC executor environment.
+    worker = new Worker('debuggerWorker.js');
+    worker.onmessage = function(message) {
+      ws.send(JSON.stringify(message.data));
+    };
+    window.onbeforeunload = function() {
+      return 'If you reload this page, it is going to break the debugging session. ' +
+        'You should press ⌘R in simulator to reload.';
+    };
+  }
+
+  function shutdownJSRuntime() {
+    if (worker) {
+      worker.terminate();
+      worker = null;
+      window.onbeforeunload = null;
+    }
+  }
 
   ws.onopen = function() {
-    if (sessionID) {
-      setStatus('Debugger session #' + sessionID + ' active.');
-      ws.send(JSON.stringify({replyID: parseInt(sessionID, 10)}));
-    } else {
-      setStatus('Waiting, press <span class="shortcut">⌘R</span> in simulator to reload and connect.');
-    }
+    setStatus(INITIAL_MESSAGE);
   };
 
   ws.onmessage = function(message) {
+    if (!message.data) {
+      return;
+    }
     var object = JSON.parse(message.data);
+
+    if (object.$event === 'client-disconnected') {
+      shutdownJSRuntime();
+      setStatus('Waiting, press <span class="shortcut">⌘R</span> in simulator to reload and connect.');
+      return;
+    }
+
     if (!object.method) {
       return;
     }
 
-    var handler = messageHandlers[object.method];
-    if (handler) {
-      // If we have a local handler, use it.
-      handler(object);
+    // Special message that asks for a new JS runtime
+    if (object.method === 'prepareJSRuntime') {
+      shutdownJSRuntime();
+      createJSRuntime();
+      ws.send(JSON.stringify({replyID: object.id}));
+      setStatus('Debugger session #' + object.id + ' active.');
+    } else if (object.method === '$disconnected') {
+      shutdownJSRuntime();
+      setStatus(INITIAL_MESSAGE);
     } else {
       // Otherwise, pass through to the worker.
       worker.postMessage(object);
     }
   };
 
-  ws.onclose = function() {
+  ws.onclose = function(e) {
+    shutdownJSRuntime();
     setStatus('Disconnected from proxy. Attempting reconnection. Is node server running?');
-
-    sessionID = null;
-    window.localStorage.removeItem('sessionID');
-    debuggerSetTimeout(connectToDebuggerProxy, 100);
+    if (e.reason) {
+      setStatus(e.reason);
+      console.warn(e.reason);
+    }
+    setTimeout(connectToDebuggerProxy, 500);
   };
-
-  worker.onmessage = function(message) {
-    ws.send(JSON.stringify(message.data));
-  }
 }
 
 connectToDebuggerProxy();
diff --git a/local-cli/server/util/webSocketProxy.js b/local-cli/server/util/webSocketProxy.js
index 66eaefb15..74c01f8ef 100644
--- a/local-cli/server/util/webSocketProxy.js
+++ b/local-cli/server/util/webSocketProxy.js
@@ -15,55 +15,59 @@ function attachToServer(server, path) {
     server: server,
     path: path
   });
-  var clients = [];
+  var debuggerSocket, clientSocket;
 
-  function sendSpecial(message) {
-    clients.forEach(function (cn) {
-      try {
-        cn.send(JSON.stringify(message));
-      } catch(e) {
-        // Sometimes this call throws 'not opened'
-      }
-    });
+  function send(dest, message) {
+    if (!dest) {
+      return;
+    }
+
+    try {
+      dest.send(message);
+    } catch(e) {
+      console.warn(e);
+      // Sometimes this call throws 'not opened'
+    }
   }
 
   wss.on('connection', function(ws) {
-    var id = Math.random().toString(15).slice(10, 20);
-    sendSpecial({$open: id});
-    clients.push(ws);
+    const {url} = ws.upgradeReq;
 
-    var allClientsExcept = function(ws) {
-      return clients.filter(function(cn) { return cn !== ws; });
-    };
-
-    ws.onerror = function() {
-      clients = allClientsExcept(ws);
-      sendSpecial({$error: id});
-    };
-
-    ws.onclose = function() {
-      clients = allClientsExcept(ws);
-      sendSpecial({$close: id});
-    };
-
-    ws.on('message', function(message) {
-      allClientsExcept(ws).forEach(function(cn) {
-        try {
-          cn.send(message);
-        } catch(e) {
-          // Sometimes this call throws 'not opened'
+    if (url.indexOf('role=debugger') > -1) {
+      if (debuggerSocket) {
+        ws.close(1011, 'Another debugger is already connected');
+        return;
+      }
+      debuggerSocket = ws;
+      debuggerSocket.onerror =
+      debuggerSocket.onclose = () => {
+        debuggerSocket = null;
+        if (clientSocket) {
+          clientSocket.close(1011, 'Debugger was disconnected');
         }
-      });
-    });
+      };
+      debuggerSocket.onmessage = ({data}) => send(clientSocket, data);
+    } else if (url.indexOf('role=client') > -1) {
+      if (clientSocket) {
+        clientSocket.onerror = clientSocket.onclose = clientSocket.onmessage = null;
+        clientSocket.close(1011, 'Another client connected');
+      }
+      clientSocket = ws;
+      clientSocket.onerror =
+      clientSocket.onclose = () => {
+        clientSocket = null;
+        send(debuggerSocket, JSON.stringify({method: '$disconnected'}));
+      };
+      clientSocket.onmessage = ({data}) => send(debuggerSocket, data);
+    } else {
+      ws.close(1011, 'Missing role param');
+    }
   });
 
   return {
     server: wss,
     isChromeConnected: function() {
-      return clients
-        .map(function(ws) { return ws.upgradeReq.headers['user-agent']; })
-        .filter(Boolean)
-        .some(function(userAgent) { return userAgent.includes('Chrome'); });
+      return !!debuggerSocket;
     }
   };
 }