diff --git a/www/code/main.js b/www/code/main.js
index 6e0270285..0686a61b9 100644
--- a/www/code/main.js
+++ b/www/code/main.js
@@ -173,7 +173,7 @@ define([
                 var titleCfg = { getHeadingText: CodeMirror.getHeadingText };
                 Title = Cryptpad.createTitle(titleCfg, config.onLocal, Cryptpad);
 
-                Metadata = Cryptpad.createMetadata(UserList, Title);
+                Metadata = Cryptpad.createMetadata(UserList, Title, null, Cryptpad);
 
                 var configTb = {
                     displayed: ['title', 'useradmin', 'spinner', 'lag', 'state', 'share', 'userlist', 'newpad', 'limit', 'upgrade'],
@@ -308,7 +308,8 @@ define([
                 if(userDoc !== "") {
                     var hjson = JSON.parse(userDoc);
 
-                    if (typeof (hjson) !== 'object' || Array.isArray(hjson)) {
+                    if (typeof (hjson) !== 'object' || Array.isArray(hjson) ||
+                        (typeof(hjson.type) !== 'undefined' && hjson.type !== 'code')) {
                         var errorText = Messages.typeError;
                         Cryptpad.errorLoadingScreen(errorText);
                         throw new Error(errorText);
diff --git a/www/common/common-metadata.js b/www/common/common-metadata.js
index d5487901c..99115fac6 100644
--- a/www/common/common-metadata.js
+++ b/www/common/common-metadata.js
@@ -1,7 +1,7 @@
 define(function () {
     var module = {};
 
-    module.create = function (UserList, Title, cfg) {
+    module.create = function (UserList, Title, cfg, Cryptpad) {
         var exp = {};
 
         exp.update = function (shjson) {
@@ -15,6 +15,14 @@ define(function () {
                 metadata = json.metadata;
             }
             if (typeof metadata === "object") {
+                if (Cryptpad) {
+                    if (typeof(metadata.type) === 'undefined') {
+                        // initialize pad type by location.pathname
+                        metadata.type = Cryptpad.getAppType();
+                    }
+                } else {
+                    console.log("Cryptpad should exist but it does not");
+                }
                 if (metadata.users) {
                     var userData = metadata.users;
                     // Update the local user data
diff --git a/www/common/common-util.js b/www/common/common-util.js
index 0bc53f5dd..242ae6fc8 100644
--- a/www/common/common-util.js
+++ b/www/common/common-util.js
@@ -139,5 +139,12 @@ define([], function () {
         return Math.floor(Math.random() * Number.MAX_SAFE_INTEGER);
     };
 
+    Util.getAppType = function () {
+        var parts = window.location.pathname.split('/')
+            .filter(function (x) { return x; });
+        if (!parts[0]) { return ''; }
+        return parts[0];
+    };
+
     return Util;
 });
diff --git a/www/common/cryptpad-common.js b/www/common/cryptpad-common.js
index fb19e0f52..424c5bf52 100644
--- a/www/common/cryptpad-common.js
+++ b/www/common/cryptpad-common.js
@@ -83,6 +83,7 @@ define([
     common.fetch = Util.fetch;
     common.throttle = Util.throttle;
     common.createRandomInteger = Util.createRandomInteger;
+    common.getAppType = Util.getAppType;
 
     // import hash utilities for export
     var createRandomHash = common.createRandomHash = Hash.createRandomHash;
@@ -906,18 +907,12 @@ define([
         common.getPinnedUsage(todo);
     };
 
-    var getAppSuffix = function () {
-        var parts = window.location.pathname.split('/')
-            .filter(function (x) { return x; });
-
-        if (!parts[0]) { return ''; }
-        return '_' + parts[0].toUpperCase();
-    };
-
     var prepareFeedback = common.prepareFeedback = function (key) {
         if (typeof(key) !== 'string') { return $.noop; }
+
+        var type = common.getAppType();
         return function () {
-            feedback(key.toUpperCase() + getAppSuffix());
+            feedback((key + (type? '_' + type: '')).toUpperCase());
         };
     };
 
diff --git a/www/pad/main.js b/www/pad/main.js
index 6538f0222..7a9ea059f 100644
--- a/www/pad/main.js
+++ b/www/pad/main.js
@@ -306,7 +306,8 @@ define([
                 hjson[3] = {
                     metadata: {
                         users: UserList.userData,
-                        defaultTitle: Title.defaultTitle
+                        defaultTitle: Title.defaultTitle,
+                        type: 'pad'
                     }
                 };
                 if (!initializing) {
@@ -450,7 +451,7 @@ define([
                 var titleCfg = { getHeadingText: getHeadingText };
                 Title = Cryptpad.createTitle(titleCfg, realtimeOptions.onLocal, Cryptpad);
 
-                Metadata = Cryptpad.createMetadata(UserList, Title);
+                Metadata = Cryptpad.createMetadata(UserList, Title, null, Cryptpad);
 
                 var configTb = {
                     displayed: ['title', 'useradmin', 'spinner', 'lag', 'state', 'share', 'userlist', 'newpad', 'limit', 'upgrade'],
diff --git a/www/poll/main.js b/www/poll/main.js
index adfe60ec3..0948ec8b4 100644
--- a/www/poll/main.js
+++ b/www/poll/main.js
@@ -430,6 +430,7 @@ define([
         });
 
         proxy.version = 1;
+        proxy.type = 'poll';
     };
 
     /*
@@ -475,6 +476,16 @@ var ready = function (info, userid, readOnly) {
     var userDoc = JSON.stringify(proxy);
     if (userDoc === "" || userDoc === "{}") { isNew = true; }
 
+    if (!isNew && typeof(proxy.type) !== 'undefined' && proxy.type !== 'poll') {
+        var errorText = Messages.typeError;
+        Cryptpad.errorLoadingScreen(errorText);
+        throw new Error(errorText);
+    }
+
+    if (typeof(proxy.type) === 'undefined') {
+        proxy.type = 'poll';
+    }
+
     var uncommitted = APP.uncommitted = {};
     prepareProxy(proxy, copyObject(Render.Example));
     prepareProxy(uncommitted, copyObject(Render.Example));
diff --git a/www/slide/main.js b/www/slide/main.js
index 9ea3925e9..6ac477e45 100644
--- a/www/slide/main.js
+++ b/www/slide/main.js
@@ -343,7 +343,7 @@ define([
                 };
                 Title = Cryptpad.createTitle(titleCfg, config.onLocal, Cryptpad);
 
-                Metadata = Cryptpad.createMetadata(UserList, Title, metadataCfg);
+                Metadata = Cryptpad.createMetadata(UserList, Title, metadataCfg, Cryptpad);
 
                 var configTb = {
                     displayed: ['title', 'useradmin', 'spinner', 'lag', 'state', 'share', 'userlist', 'newpad', 'limit', 'upgrade'],
@@ -557,7 +557,8 @@ define([
                     var hjson = JSON.parse(userDoc);
                     newDoc = hjson.content;
 
-                    if (typeof (hjson) !== 'object' || Array.isArray(hjson)) {
+                    if (typeof (hjson) !== 'object' || Array.isArray(hjson) ||
+                        (typeof(hjson.type) !== 'undefined' && hjson.type !== 'slide')) {
                         var errorText = Messages.typeError;
                         Cryptpad.errorLoadingScreen(errorText);
                         throw new Error(errorText);
diff --git a/www/whiteboard/main.js b/www/whiteboard/main.js
index 1949549af..c399d5c3f 100644
--- a/www/whiteboard/main.js
+++ b/www/whiteboard/main.js
@@ -293,7 +293,7 @@ window.canvas = canvas;
 
             Title = Cryptpad.createTitle({}, config.onLocal, Cryptpad);
 
-            Metadata = Cryptpad.createMetadata(UserList, Title, metadataCfg);
+            Metadata = Cryptpad.createMetadata(UserList, Title, metadataCfg, Cryptpad);
 
             var configTb = {
                 displayed: ['title', 'useradmin', 'spinner', 'lag', 'state', 'share', 'userlist', 'newpad', 'limit', 'upgrade'],
@@ -384,7 +384,8 @@ window.canvas = canvas;
                 metadata: {
                     users: UserList.userData,
                     palette: palette,
-                    defaultTitle: Title.defaultTitle
+                    defaultTitle: Title.defaultTitle,
+                    type: 'whiteboard',
                 }
             };
             if (!initializing) {
@@ -413,6 +414,14 @@ window.canvas = canvas;
             var isNew = false;
             var userDoc = module.realtime.getUserDoc();
             if (userDoc === "" || userDoc === "{}") { isNew = true; }
+            else {
+                var hjson = JSON.parse(userDoc);
+                if (typeof(hjson) !== 'object' || Array.isArray(hjson) ||
+                    (typeof(hjson.type) !== 'undefined' && hjson.type !== whiteboard)) {
+                    Cryptpad.errorLoadingScreen(Messages.typeError);
+                    throw new Error(Messages.typeError);
+                }
+            }
 
             Cryptpad.removeLoadingScreen();
             setEditable(true);