Specifying a GCM API Key for Android
A Google Cloud Messaging (GCM) API key is required if you want to support mobile device management (MDM) and push notifications on Android devices. For more information on how to obtain such a key, see
http://developer.android.com/google/gcm/gs.html.
To specify the GCM API key for Android
1. Click 
and then Domains. 2. On the All Domains page, click the entry for the default domain.
3. On the Domain Details page, click Edit Domain.
4. In the GCM API Key field, specify the API key.
5. Click Update Site.
