diff --git a/b2g/app/b2g.js b/b2g/app/b2g.js
index e741e0ccb922..f1218a9a8062 100644
--- a/b2g/app/b2g.js
+++ b/b2g/app/b2g.js
@@ -378,6 +378,9 @@ pref("dom.sms.enabled", true);
 // Temporary permission hack for WebContacts
 pref("dom.mozContacts.enabled", true);
 
+// WebAlarms
+pref("dom.mozAlarms.enabled", true);
+
 // WebSettings
 pref("dom.mozSettings.enabled", true);
 
diff --git a/b2g/chrome/content/shell.js b/b2g/chrome/content/shell.js
index 2e9bba80cfd9..99b0c4fadbbe 100644
--- a/b2g/chrome/content/shell.js
+++ b/b2g/chrome/content/shell.js
@@ -51,7 +51,7 @@ function addPermissions(urls) {
     'indexedDB-unlimited', 'webapps-manage', 'offline-app', 'pin-app',
     'websettings-read', 'websettings-readwrite',
     'content-camera', 'webcontacts-manage', 'wifi-manage', 'desktop-notification',
-    'geolocation', 'device-storage'
+    'geolocation', 'device-storage', 'alarms'
   ];
   urls.forEach(function(url) {
     url = url.trim();
diff --git a/b2g/installer/package-manifest.in b/b2g/installer/package-manifest.in
index 6411adae027a..42bd2f85d5ed 100644
--- a/b2g/installer/package-manifest.in
+++ b/b2g/installer/package-manifest.in
@@ -163,6 +163,7 @@
 #endif
 @BINPATH@/components/dom_canvas.xpt
 @BINPATH@/components/dom_contacts.xpt
+@BINPATH@/components/dom_alarm.xpt
 @BINPATH@/components/dom_core.xpt
 @BINPATH@/components/dom_css.xpt
 @BINPATH@/components/dom_devicestorage.xpt
@@ -319,6 +320,8 @@
 @BINPATH@/components/BrowserElementParent.js
 @BINPATH@/components/ContactManager.js
 @BINPATH@/components/ContactManager.manifest
+@BINPATH@/components/AlarmsManager.js
+@BINPATH@/components/AlarmsManager.manifest
 @BINPATH@/components/FeedProcessor.manifest
 @BINPATH@/components/FeedProcessor.js
 @BINPATH@/components/BrowserFeeds.manifest
diff --git a/browser/installer/package-manifest.in b/browser/installer/package-manifest.in
index ab86fd3a4bb2..46208503d7b3 100644
--- a/browser/installer/package-manifest.in
+++ b/browser/installer/package-manifest.in
@@ -173,6 +173,7 @@
 #endif
 @BINPATH@/components/dom_canvas.xpt
 @BINPATH@/components/dom_contacts.xpt
+@BINPATH@/components/dom_alarm.xpt
 @BINPATH@/components/dom_core.xpt
 @BINPATH@/components/dom_css.xpt
 @BINPATH@/components/dom_devicestorage.xpt
@@ -472,6 +473,8 @@
 
 @BINPATH@/components/ContactManager.js
 @BINPATH@/components/ContactManager.manifest
+@BINPATH@/components/AlarmsManager.js
+@BINPATH@/components/AlarmsManager.manifest
 #ifdef ENABLE_MARIONETTE
 @BINPATH@/chrome/marionette@JAREXT@
 @BINPATH@/chrome/marionette.manifest
diff --git a/dom/Makefile.in b/dom/Makefile.in
index 71301c6da298..e8955b4ef4e4 100644
--- a/dom/Makefile.in
+++ b/dom/Makefile.in
@@ -50,6 +50,7 @@ DIRS += \
   battery \
   browser-element \
   contacts \
+  alarm \
   devicestorage \
   file \
   media \
diff --git a/dom/alarm/AlarmsManager.js b/dom/alarm/AlarmsManager.js
new file mode 100644
index 000000000000..3052fd139773
--- /dev/null
+++ b/dom/alarm/AlarmsManager.js
@@ -0,0 +1,75 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { classes: Cc, interfaces: Ci, utils: Cu, results: Cr } = Components;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/DOMRequestHelper.jsm");
+
+const ALARMSMANAGER_CONTRACTID = "@mozilla.org/alarmsManager;1";
+const ALARMSMANAGER_CID        = Components.ID("{fea1e884-9b05-11e1-9b64-87a7016c3860}");
+const nsIDOMMozAlarmsManager   = Ci.nsIDOMMozAlarmsManager;
+const nsIClassInfo             = Ci.nsIClassInfo;
+
+function AlarmsManager()
+{
+}
+
+AlarmsManager.prototype = {
+
+  __proto__: DOMRequestIpcHelper.prototype,
+
+  classID : ALARMSMANAGER_CID,
+
+  QueryInterface : XPCOMUtils.generateQI([nsIDOMMozAlarmsManager, Ci.nsIDOMGlobalPropertyInitializer]),
+
+  classInfo : XPCOMUtils.generateCI({ classID: ALARMSMANAGER_CID,
+                                      contractID: ALARMSMANAGER_CONTRACTID,
+                                      classDescription: "AlarmsManager",
+                                      interfaces: [nsIDOMMozAlarmsManager],
+                                      flags: nsIClassInfo.DOM_OBJECT }),
+
+  add: function add(aDate, aRespectTimezone, aData) {
+    return null;
+  },
+
+  remove: function remove(aId) {
+    return;
+  },
+
+  getAll: function getAll() {
+    return null;
+  },
+
+  // nsIDOMGlobalPropertyInitializer implementation
+  init: function init(aWindow) {
+    // Set navigator.mozAlarms to null.
+    if (!Services.prefs.getBoolPref("dom.mozAlarms.enabled"))
+      return null;
+
+    let principal = aWindow.document.nodePrincipal;
+    let secMan = Cc["@mozilla.org/scriptsecuritymanager;1"].getService(Ci.nsIScriptSecurityManager);
+
+    let perm = principal == secMan.getSystemPrincipal() ? 
+      Ci.nsIPermissionManager.ALLOW_ACTION : Services.perms.testExactPermission(principal.URI, "alarms");
+
+    // Only pages with perm set can use the alarms.
+    this.hasPrivileges = perm == Ci.nsIPermissionManager.ALLOW_ACTION;
+
+    if (!this.hasPrivileges)
+      return null;
+
+    // Add the valid messages to be listened.
+    this.initHelper(aWindow, []);
+  },
+
+  // Called from DOMRequestIpcHelper.
+  uninit: function uninit() {
+  },
+}
+
+const NSGetFactory = XPCOMUtils.generateNSGetFactory([AlarmsManager])
diff --git a/dom/alarm/AlarmsManager.manifest b/dom/alarm/AlarmsManager.manifest
new file mode 100644
index 000000000000..18cd0293fbfd
--- /dev/null
+++ b/dom/alarm/AlarmsManager.manifest
@@ -0,0 +1,3 @@
+component {fea1e884-9b05-11e1-9b64-87a7016c3860} AlarmsManager.js
+contract @mozilla.org/alarmsManager;1 {fea1e884-9b05-11e1-9b64-87a7016c3860}
+category JavaScript-navigator-property mozAlarms @mozilla.org/alarmsManager;1
diff --git a/dom/alarm/Makefile.in b/dom/alarm/Makefile.in
new file mode 100644
index 000000000000..e11c90e9cb09
--- /dev/null
+++ b/dom/alarm/Makefile.in
@@ -0,0 +1,33 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+DEPTH       = ../..
+topsrcdir   = @top_srcdir@
+srcdir      = @srcdir@
+VPATH       = @srcdir@
+
+include $(DEPTH)/config/autoconf.mk
+
+MODULE              = dom
+XPIDL_MODULE        = dom_alarm
+LIBRARY_NAME        = domalarm_s
+LIBXUL_LIBRARY      = 1
+
+include $(topsrcdir)/dom/dom-config.mk
+
+EXTRA_COMPONENTS =       \
+  AlarmsManager.js       \
+  AlarmsManager.manifest \
+  $(NULL)
+
+XPIDLSRCS =               \
+  nsIDOMAlarmsManager.idl \
+  $(NULL)
+
+ifdef ENABLE_TESTS
+DIRS += test
+endif
+
+include $(topsrcdir)/config/config.mk
+include $(topsrcdir)/config/rules.mk
diff --git a/dom/alarm/nsIDOMAlarmsManager.idl b/dom/alarm/nsIDOMAlarmsManager.idl
new file mode 100644
index 000000000000..4ef68691d1ea
--- /dev/null
+++ b/dom/alarm/nsIDOMAlarmsManager.idl
@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "domstubs.idl"
+
+interface nsIDOMDOMRequest;
+
+[scriptable, uuid(fea1e884-9b05-11e1-9b64-87a7016c3860)]
+interface nsIDOMMozAlarmsManager : nsISupports
+{
+  nsIDOMDOMRequest getAll();
+  nsIDOMDOMRequest add(in jsval date, in DOMString respectTimezone, [optional] in jsval data);
+  void remove(in unsigned long id);
+};
diff --git a/dom/alarm/test/Makefile.in b/dom/alarm/test/Makefile.in
new file mode 100644
index 000000000000..b58809903d9b
--- /dev/null
+++ b/dom/alarm/test/Makefile.in
@@ -0,0 +1,25 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+
+DEPTH            = ../../..
+topsrcdir        = @top_srcdir@
+srcdir           = @srcdir@
+VPATH            = @srcdir@
+
+relativesrcdir   = dom/alarm/test
+
+include $(DEPTH)/config/autoconf.mk
+
+DIRS = \
+  $(NULL)
+
+include $(topsrcdir)/config/rules.mk
+
+_TEST_FILES = \
+  test_alarm_permitted_app.html \
+  test_alarm_non_permitted_app.html \
+  $(NULL)
+
+libs:: $(_TEST_FILES)
+	$(INSTALL) $(foreach f,$^,"$f") $(DEPTH)/_tests/testing/mochitest/tests/$(relativesrcdir)
diff --git a/dom/alarm/test/test_alarm_non_permitted_app.html b/dom/alarm/test/test_alarm_non_permitted_app.html
new file mode 100644
index 000000000000..1d6409e5f149
--- /dev/null
+++ b/dom/alarm/test/test_alarm_non_permitted_app.html
@@ -0,0 +1,35 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test Non-Permitted Application for Alarm API</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content" style="display: none"></div>
+<pre id="test">
+<script type="application/javascript">
+
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+
+SpecialPowers.pushPrefEnv({"set": [["dom.mozAlarms.enabled", true]]}, function() {
+  SpecialPowers.removePermission("alarms", document);
+
+  // mozAlarms is intalled on all platforms except Android for the moment.
+  if (navigator.appVersion.indexOf("Android") != -1) {
+    ok(!('mozAlarms' in navigator), "navigator.mozAlarms should not exist");
+  } else {
+    ok('mozAlarms' in navigator, "navigator.mozAlarms should exist");
+    is(navigator.mozAlarms, null, "navigator.mozAlarms should return null");
+  }
+
+  SimpleTest.finish();
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/alarm/test/test_alarm_permitted_app.html b/dom/alarm/test/test_alarm_permitted_app.html
new file mode 100644
index 000000000000..25d7f83ca985
--- /dev/null
+++ b/dom/alarm/test/test_alarm_permitted_app.html
@@ -0,0 +1,38 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test Permitted Application for Alarm API</title>
+  <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<p id="display"></p>
+<div id="content" style="display: none"></div>
+<pre id="test">
+<script type="application/javascript">
+
+"use strict";
+
+SimpleTest.waitForExplicitFinish();
+
+SpecialPowers.pushPrefEnv({"set": [["dom.mozAlarms.enabled", true]]}, function() {
+  SpecialPowers.addPermission("alarms", true, document);
+
+  // mozAlarms is intalled on all platforms except Android for the moment.
+  if (navigator.appVersion.indexOf("Android") != -1) {
+    ok(!('mozAlarms' in navigator), "navigator.mozAlarms should not exist");
+  } else {
+    ok('mozAlarms' in navigator, "navigator.mozAlarms should exist");
+    ok(navigator.mozAlarms, "navigator.mozAlarms should return an object");
+    ok(navigator.mozAlarms instanceof Components.interfaces.nsIDOMMozAlarmsManager,
+      "navigator.mozAlarms should be an nsIDOMMozAlarmsManager object");
+  }
+
+  SpecialPowers.removePermission("alarms", document);
+  SimpleTest.finish();
+});
+
+</script>
+</pre>
+</body>
+</html>
diff --git a/dom/dom-config.mk b/dom/dom-config.mk
index 1d4cdab4075a..f91f51a1ea04 100644
--- a/dom/dom-config.mk
+++ b/dom/dom-config.mk
@@ -12,6 +12,7 @@ DOM_SRCDIRS = \
   dom/settings \
   dom/sms/src \
   dom/contacts \
+  dom/alarm \
   dom/src/events \
   dom/src/storage \
   dom/src/offline \
diff --git a/dom/tests/mochitest/general/test_interfaces.html b/dom/tests/mochitest/general/test_interfaces.html
index 26d7621fea51..a38bf368d80b 100644
--- a/dom/tests/mochitest/general/test_interfaces.html
+++ b/dom/tests/mochitest/general/test_interfaces.html
@@ -89,6 +89,7 @@ var interfaceNamesInGlobalScope =
     "WebGLExtensionLoseContext",
     "CanvasRenderingContext2D",
     "SVGPathSegLinetoVerticalRel",
+    "MozAlarmsManager",
     "MozPowerManager",
     "SVGElement",
     "GeoPositionError",
diff --git a/layout/build/Makefile.in b/layout/build/Makefile.in
index 9daa83aaee69..1cf716c8c0fb 100644
--- a/layout/build/Makefile.in
+++ b/layout/build/Makefile.in
@@ -62,6 +62,7 @@ SHARED_LIBRARY_LIBS = \
 	$(DEPTH)/dom/base/$(LIB_PREFIX)jsdombase_s.$(LIB_SUFFIX) \
 	$(DEPTH)/dom/battery/$(LIB_PREFIX)dom_battery_s.$(LIB_SUFFIX) \
 	$(DEPTH)/dom/contacts/$(LIB_PREFIX)jsdomcontacts_s.$(LIB_SUFFIX) \
+	$(DEPTH)/dom/alarm/$(LIB_PREFIX)domalarm_s.$(LIB_SUFFIX) \
 	$(DEPTH)/dom/devicestorage/$(LIB_PREFIX)domdevicestorage_s.$(LIB_SUFFIX) \
 	$(DEPTH)/dom/file/$(LIB_PREFIX)domfile_s.$(LIB_SUFFIX) \
 	$(DEPTH)/dom/power/$(LIB_PREFIX)dom_power_s.$(LIB_SUFFIX) \
diff --git a/modules/libpref/src/init/all.js b/modules/libpref/src/init/all.js
index 0c9e8a25e4bf..876c01d888a8 100644
--- a/modules/libpref/src/init/all.js
+++ b/modules/libpref/src/init/all.js
@@ -3578,6 +3578,9 @@ pref("dom.sms.whitelist", "");
 pref("dom.mozContacts.enabled", false);
 pref("dom.mozContacts.whitelist", "");
 
+// WebAlarms
+pref("dom.mozAlarms.enabled", false);
+
 // WebSettings
 pref("dom.mozSettings.enabled", false);
 
diff --git a/toolkit/toolkit-makefiles.sh b/toolkit/toolkit-makefiles.sh
index 15bcdb761106..c623bd84a047 100644
--- a/toolkit/toolkit-makefiles.sh
+++ b/toolkit/toolkit-makefiles.sh
@@ -35,6 +35,7 @@ MAKEFILES_dom="
   dom/interfaces/xbl/Makefile
   dom/interfaces/xpath/Makefile
   dom/interfaces/xul/Makefile
+  dom/alarm/Makefile
   dom/base/Makefile
   dom/battery/Makefile
   dom/file/Makefile
@@ -709,6 +710,7 @@ if [ "$ENABLE_TESTS" ]; then
     docshell/test/Makefile
     docshell/test/chrome/Makefile
     docshell/test/navigation/Makefile
+    dom/alarm/test/Makefile
     dom/battery/test/Makefile
     dom/indexedDB/test/Makefile
     dom/indexedDB/test/unit/Makefile