diff --git a/src/MatrixClientPeg.js b/src/MatrixClientPeg.js
index 6b36e67e6b..36ccd0a7dc 100644
--- a/src/MatrixClientPeg.js
+++ b/src/MatrixClientPeg.js
@@ -23,6 +23,16 @@ var matrixClient = null;
 
 var localStorage = window.localStorage;
 
+function deviceId() {
+    var id = Math.floor(Math.random()*16777215).toString(16);
+    id = "W" + "000000".substring(id.length) + id;
+    if (localStorage) {
+        id = localStorage.getItem("mx_device_id") || id;
+        localStorage.setItem("mx_device_id", id);
+    }
+    return id;
+}
+
 function createClient(hs_url, is_url, user_id, access_token) {
     var opts = {
         baseUrl: hs_url,
@@ -31,6 +41,11 @@ function createClient(hs_url, is_url, user_id, access_token) {
         userId: user_id
     };
 
+    if (localStorage) {
+        opts.sessionStore = new Matrix.WebStorageSessionStore(localStorage);
+        opts.deviceId = deviceId();
+    }
+
     matrixClient = Matrix.createClient(opts);
 }
 
@@ -49,6 +64,10 @@ module.exports = {
         return matrixClient;
     },
 
+    unset: function() {
+        matrixClient = null;
+    },
+
     replaceUsingUrls: function(hs_url, is_url) {
         matrixClient = Matrix.createClient({
             baseUrl: hs_url,
@@ -57,10 +76,16 @@ module.exports = {
     },
 
     replaceUsingAccessToken: function(hs_url, is_url, user_id, access_token) {
-        createClient(hs_url, is_url, user_id, access_token);
         if (localStorage) {
             try {
                 localStorage.clear();
+            } catch (e) {
+                console.warn("Error using local storage");
+            }
+        }
+        createClient(hs_url, is_url, user_id, access_token);
+        if (localStorage) {
+            try {
                 localStorage.setItem("mx_hs_url", hs_url);
                 localStorage.setItem("mx_is_url", is_url);
                 localStorage.setItem("mx_user_id", user_id);
diff --git a/src/RoomListSorter.js b/src/RoomListSorter.js
index bc7a001670..730a0de18b 100644
--- a/src/RoomListSorter.js
+++ b/src/RoomListSorter.js
@@ -17,7 +17,12 @@ limitations under the License.
 'use strict';
 
 function tsOfNewestEvent(room) {
-    return room.timeline[room.timeline.length - 1].getTs();
+    if (room.timeline.length) {
+        return room.timeline[room.timeline.length - 1].getTs();
+    }
+    else {
+        return Number.MAX_SAFE_INTEGER;
+    }
 }
 
 function mostRecentActivityFirst(roomList) {