To expand on this answer , there is currently no official GCM library in Mono for Android. The GCM library is optional in the Android SDK, and that Extra does not have an official version in Mono for Android.
Since C2DM is deprecated, how is this possible? Two reasons:
Firstly, there is an unofficial GCM library for Mono for Android . This is part of Push # and includes the GCMBaseIntentService and GCMRegistrar , which come with the Java GCM library. These classes are direct ports of the Android SDK versions, so if you use them, you can follow the GCM launch guide.
Secondly, GCM is doable even without a real GCM library . Under the hood, this is very similar to C2DM, with only a few changes in intentions and permissions. The GCM library in the Android SDK is just a bunch of helpers for handling GCM registrations and GCM messages.
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