How does the GCM or cloud server know if it's the same tablet that's trying to register again? i mean, you only send the sender id, the same sender id for the same app right? so how does the server know if it's a different device, does the GCMRegistrar also implicitly send a certain device ID together with the sender ID and the package name?
I'm puzzled how it saves the registration. What if I uninstall the app on my tablet, will it also remove the registration ID in the gcm server? What if I reinstall the app after uninstalling, will it provide the same registration ID or create a new one? how will it know that it's the same device?
Also I don't know that's the use of unregistering from GCM. why would I do that unless my app is being uninstalled?
Thank you very much! :)