Amazon SNS: “Platform credentials are invalid” when re-entering a GCM API key that previously worked

Question

We have been using Amazon SNS to send Android push notifications since April this year.

Pushes have sent with no problem, however there has never been any record of

Answer 1

For those starting a new project and wondering why it is still invalid, make sure the application Key restriction is set to Android apps. In my case, it was at only set to None and when I switched to Android apps, it worked after 5 to 10min after updating it. You'll need to add your package name and SHA-1 certificate fingerprint.