This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
Returns, through the callback function, the apps that were installed by the calling domain. This allows an app directory or store to determine which app it has installed on behalf of the current user.
navigator.mozApps.getInstalledBy( callback )
A callback function that is invoked with an array of the
Appobjects installed by the calling origin.