GCM and app updates: should I be re-registering in every activity or just the main one?
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Ok, so I know that if the app gets updated, I should re-register with GCM because the old key might be invalid at that point. My question is, when an app updates, are all open activities closed and can I count on the main activity being started again (ie i can just put the version check & re-register in the onCreate of that activity), or are all the open activities going to continue running and I have to put that re-register check in all the onStarts of those activities? (sorry i dont have an android phone to test this out with and emulators dont connect to google play)