diff --git a/step-06/index.js b/step-06/index.js
index c0c25ce..ae178ae 100644
--- a/step-06/index.js
+++ b/step-06/index.js
@@ -60,8 +60,12 @@ io.sockets.on('connection', function(socket) {
     }
   });
 
-  socket.on('bye', function(){
-    console.log('received bye');
+  socket.on('disconnect', function(reason) {
+    console.log(`Peer or server disconnected. Reason: ${reason}.`);
+    socket.broadcast.emit('bye');
   });
 
+  socket.on('bye', function(room) {
+    console.log(`Peer said bye on room ${room}.`);
+  });
 });
diff --git a/step-06/js/main.js b/step-06/js/main.js
index 0d44f93..9ba7701 100644
--- a/step-06/js/main.js
+++ b/step-06/js/main.js
@@ -29,6 +29,10 @@ snapBtn.addEventListener('click', snapPhoto);
 sendBtn.addEventListener('click', sendPhoto);
 snapAndSendBtn.addEventListener('click', snapAndSend);
 
+// Disable send buttons by default.
+sendBtn.disabled = true;
+snapAndSendBtn.disabled = true;
+
 // Create a random room if not already present in the URL.
 var isInitiator;
 var room = window.location.hash.substring(1);
@@ -82,13 +86,36 @@ socket.on('message', function(message) {
   signalingMessageCallback(message);
 });
 
-// Join a room
+// Joining a room.
 socket.emit('create or join', room);
 
 if (location.hostname.match(/localhost|127\.0\.0/)) {
   socket.emit('ipaddr');
 }
 
+// Leaving rooms and disconnecting from peers.
+socket.on('disconnect', function(reason) {
+  console.log(`Disconnected: ${reason}.`);
+  sendBtn.disabled = true;
+  snapAndSendBtn.disabled = true;
+});
+
+socket.on('bye', function(room) {
+  console.log(`Peer leaving room ${room}.`);
+  sendBtn.disabled = true;
+  snapAndSendBtn.disabled = true;
+  // If peer did not create the room, re-enter to be creator.
+  if (!isInitiator) {
+    window.location.reload();
+  }
+});
+
+window.addEventListener('unload', function() {
+  console.log(`Unloading window. Notifying peers in ${room}.`);
+  socket.emit('bye', room);
+});
+
+
 /**
 * Send message to signaling server
 */
@@ -162,9 +189,7 @@ function signalingMessageCallback(message) {
       candidate: message.candidate
     }));
 
-  } else if (message === 'bye') {
-// TODO: cleanup RTC connection?
-}
+  }
 }
 
 function createPeerConnection(isInitiator, config) {
@@ -216,8 +241,16 @@ function onDataChannelCreated(channel) {
 
   channel.onopen = function() {
     console.log('CHANNEL opened!!!');
+    sendBtn.disabled = false;
+    snapAndSendBtn.disabled = false;
   };
 
+  channel.onclose = function () {
+    console.log('Channel closed.');
+    sendBtn.disabled = true;
+    snapAndSendBtn.disabled = true;
+  }
+
   channel.onmessage = (adapter.browserDetails.browser === 'firefox') ?
   receiveDataFirefoxFactory() : receiveDataChromeFactory();
 }
@@ -304,6 +337,16 @@ len = img.data.byteLength,
 n = len / CHUNK_LEN | 0;
 
 console.log('Sending a total of ' + len + ' byte(s)');
+
+if (!dataChannel) {
+  logError('Connection has not been initiated. ' +
+    'Get two peers in the same room first');
+  return;
+} else if (dataChannel.readyState === 'closed') {
+  logError('Connection was lost. Peer closed the connection.');
+  return;
+}
+
 dataChannel.send(len);
 
 // split the photo and send in chunks of about 64KB
@@ -357,5 +400,10 @@ function randomToken() {
 }
 
 function logError(err) {
-  console.log(err.toString(), err);
+  if (!err) return;
+  if (typeof err === 'string') {
+    console.warn(err);
+  } else {
+    console.warn(err.toString(), err);
+  }
 }