diff --git a/mobile/android/chrome/content/WebAppRT.js b/mobile/android/chrome/content/WebAppRT.js
index d81c1c6259c..c6a96e3929a 100644
--- a/mobile/android/chrome/content/WebAppRT.js
+++ b/mobile/android/chrome/content/WebAppRT.js
@@ -6,6 +6,8 @@ let Ci = Components.interfaces;
 let Cu = Components.utils;
 
 Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/FileUtils.jsm");
+Cu.import("resource://gre/modules/NetUtil.jsm");
 
 function pref(name, value) {
   return {
@@ -15,6 +17,8 @@ function pref(name, value) {
 }
 
 var WebAppRT = {
+  DEFAULT_PREFS_FILENAME: "default-prefs.js",
+
   prefs: [
     // Disable all add-on locations other than the profile (which can't be disabled this way)
     pref("extensions.enabledScopes", 1),
@@ -26,33 +30,60 @@ var WebAppRT = {
     pref("toolkit.telemetry.prompted", 2)
   ],
 
-  init: function(isUpdate) {
+  init: function(isUpdate, url) {
     this.deck = document.getElementById("browsers");
     this.deck.addEventListener("click", this, false, true);
 
     // on first run, update any prefs
     if (isUpdate == "new") {
-      this.prefs.forEach(function(aPref) {
-        switch (typeof aPref.value) {
-          case "string":
-            Services.prefs.setCharPref(aPref.name, aPref.value);
-            break;
-          case "boolean":
-            Services.prefs.setBoolPref(aPref.name, aPref.value);
-            break;
-          case "number":
-            Services.prefs.setIntPref(aPref.name, aPref.value);
-            break;
-        }
-      });
+      this.getDefaultPrefs().forEach(this.addPref);
 
       // update the blocklist url to use a different app id
-      var blocklist = Services.prefs.getCharPref("extensions.blocklist.url");
+      let blocklist = Services.prefs.getCharPref("extensions.blocklist.url");
       blocklist = blocklist.replace(/%APP_ID%/g, "webapprt-mobile@mozilla.org");
       Services.prefs.setCharPref("extensions.blocklist.url", blocklist);
     }
   },
 
+  getDefaultPrefs: function() {
+    // read default prefs from the disk
+    try {
+      let defaultPrefs = [];
+      try {
+          defaultPrefs = this.readDefaultPrefs(FileUtils.getFile("ProfD", [this.DEFAULT_PREFS_FILENAME]));
+      } catch(ex) {
+          // this can throw if the defaultprefs.js file doesn't exist
+      }
+      for (let i = 0; i < defaultPrefs.length; i++) {
+        this.prefs.push(defaultPrefs[i]);
+      }
+    } catch(ex) {
+      console.log("Error reading defaultPrefs file: " + ex);
+    }
+    return this.prefs;
+  },
+
+  readDefaultPrefs: function webapps_readDefaultPrefs(aFile) {
+    let fstream = Cc["@mozilla.org/network/file-input-stream;1"].createInstance(Ci.nsIFileInputStream);
+    fstream.init(aFile, -1, 0, 0);
+    let prefsString = NetUtil.readInputStreamToString(fstream, fstream.available(), {});
+    return JSON.parse(prefsString);
+  },
+
+  addPref: function(aPref) {
+    switch (typeof aPref.value) {
+      case "string":
+        Services.prefs.setCharPref(aPref.name, aPref.value);
+        break;
+      case "boolean":
+        Services.prefs.setBoolPref(aPref.name, aPref.value);
+        break;
+      case "number":
+        Services.prefs.setIntPref(aPref.name, aPref.value);
+        break;
+    }
+  },
+
   handleEvent: function(event) {
     let target = event.target;
   
diff --git a/mobile/android/chrome/content/browser.js b/mobile/android/chrome/content/browser.js
index 19947abfd76..2fdd20d37ce 100644
--- a/mobile/android/chrome/content/browser.js
+++ b/mobile/android/chrome/content/browser.js
@@ -27,6 +27,11 @@ XPCOMUtils.defineLazyGetter(this, "DebuggerServer", function() {
   return DebuggerServer;
 });
 
+XPCOMUtils.defineLazyGetter(this, "NetUtil", function() {
+  Cu.import("resource://gre/modules/NetUtil.jsm");
+  return NetUtil;
+});
+
 // Lazily-loaded browser scripts:
 [
   ["HelperApps", "chrome://browser/content/HelperApps.js"],
@@ -5916,7 +5921,9 @@ var WebappsUI = {
     Services.obs.removeObserver(this, "webapps-sync-install");
     Services.obs.removeObserver(this, "webapps-sync-uninstall");
   },
-  
+
+  DEFAULT_PREFS_FILENAME: "default-prefs.js",
+
   observe: function observe(aSubject, aTopic, aData) {
     let data = JSON.parse(aData);
     switch (aTopic) {
@@ -6008,8 +6015,8 @@ var WebappsUI = {
       // Add a homescreen shortcut -- we can't use createShortcut, since we need to pass
       // a unique ID for Android webapp allocation
       this.makeBase64Icon(this.getBiggestIcon(manifest.icons, Services.io.newURI(aData.app.origin, null, null)),
-        function(icon) {
-          var profilePath = sendMessageToJava({
+        (function(icon) {
+          let profilePath = sendMessageToJava({
             gecko: {
               type: "WebApps:Install",
               name: manifest.name,
@@ -6020,18 +6027,46 @@ var WebappsUI = {
           });
   
           // if java returned a profile path to us, try to use it to pre-populate the app cache
-          var file = null;
+          let file = null;
           if (profilePath) {
-            var file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);
+            file = Cc["@mozilla.org/file/local;1"].createInstance(Ci.nsILocalFile);
             file.initWithPath(profilePath);
+
+            // build any app specific default prefs
+            let prefs = [];
+            if (manifest.orientation)
+              prefs.push({name:"app.orientation.default", value: manifest.orientation});
+
+            // write them into the app profile
+            let defaultPrefsFile = file.clone();
+            defaultPrefsFile.append(this.DEFAULT_PREFS_FILENAME);
+            this.writeDefaultPrefs(defaultPrefsFile, prefs);
           }
           DOMApplicationRegistry.confirmInstall(aData, false, file);
-        });
+        }).bind(this));
     } else {
       DOMApplicationRegistry.denyInstall(aData);
     }
   },
-  
+
+  writeDefaultPrefs: function webapps_writeDefaultPrefs(aFile, aPrefs) {
+    if (aPrefs.length > 0) {
+      let data = JSON.stringify(aPrefs);
+
+      var ostream = Cc["@mozilla.org/network/file-output-stream;1"].createInstance(Ci.nsIFileOutputStream);
+      ostream.init(aFile, -1, -1, 0);
+
+      let istream = Cc["@mozilla.org/io/string-input-stream;1"].createInstance(Ci.nsIStringInputStream);
+      istream.setData(data, data.length);
+
+      NetUtil.asyncCopy(istream, ostream, function(aResult) {
+        if (!Components.isSuccessCode(aResult)) {
+          console.log("Error writing default prefs: " + aResult);
+        }
+      });
+    }
+  },
+
   openURL: function openURL(aURI, aOrigin) {
     sendMessageToJava({
       gecko: {