--- a/devtools/client/definitions.js
+++ b/devtools/client/definitions.js
@@ -457,19 +457,19 @@ Tools.accessibility = {
 };
 
 Tools.application = {
   id: "application",
   ordinal: 15,
   visibilityswitch: "devtools.application.enabled",
   icon: "chrome://devtools/skin/images/tool-application.svg",
   url: "chrome://devtools/content/application/index.html",
-  label: "Application",
-  panelLabel: "Application",
-  tooltip: "Application",
+  label: l10n("application.label"),
+  panelLabel: l10n("application.panellabel"),
+  tooltip: l10n("application.tooltip"),
   inMenu: false,
   hiddenInOptions: true,
 
   isTargetSupported: function(target) {
     return target.isLocalTab;
   },
 
   build: function(iframeWindow, toolbox) {

--- a/devtools/client/locales/en-US/startup.properties
+++ b/devtools/client/locales/en-US/startup.properties
@@ -263,16 +263,30 @@ accessibility.panelLabel=Accessibility P
 accessibility.accesskey=y
 
 # LOCALIZATION NOTE (accessibility.tooltip2):
 # This string is displayed in the tooltip of the tab when the Accessibility is
 # displayed inside the developer tools window.
 # Keyboard shortcut for Accessibility panel will be shown inside the brackets.
 accessibility.tooltip2=Accessibility
 
+# LOCALIZATION NOTE (application.label):
+# This string is displayed in the title of the tab when the Application panel
+# is displayed inside the developer tools window and in the Developer Tools Menu.
+application.label=Application
+
+# LOCALIZATION NOTE (application.panelLabel):
+# This is used as the label for the toolbox panel.
+application.panelLabel=Application Panel
+
+# LOCALIZATION NOTE (application.tooltip):
+# This string is displayed in the tooltip of the tab when the Application panel is
+# displayed inside the developer tools window.
+application.tooltip=Application Panel
+
 # LOCALIZATION NOTE (toolbox.buttons.responsive):
 # This is the tooltip of the button in the toolbox toolbar that toggles
 # the Responsive mode.
 # Keyboard shortcut will be shown inside brackets.
 toolbox.buttons.responsive = Responsive Design Mode (%S)
 
 # LOCALIZATION NOTE (toolbox.buttons.paintflashing):
 # This is the tooltip of the paintflashing button in the toolbox toolbar