title: Android GCM Server error: Device Subscription Expired
body: <p>On sending notifications to an Android device via GCM I am getting the following response:</p>
  
  <p>Device Subscription Expired: PushSharp.Android.GcmPushService -> AppId</p>
  
  <p>Due to this issue I experience random issues on the phone. For example, the app receives extra call backs on the receiver. </p>
  
  <p>Can someone please provide more details about this error? When does it occur? Is it similar to device id registration? What needs to be done to handle this situation?</p>
  
  <p>Thanks!</p>