Some changes are coming to Google Play Games this year, and they'll affect both users and developers. As announced on the Android Developer Blog, the changes are intended "to reduce sign-in friction and unnecessary permission requests for players by moving the Games APIs to a new model."
Here's the deal:
- Google Play Games won't require the user's account to have been upgraded to Google+. There's a good chance if you're reading this that's a moot point, but once the change takes place new users will get a player ID that's not tied to Google+.
- You'll only have to sign in once per account — not once per game. That one's great for users.
- And you'll be automatically signed in, though you can turn off that in settings if you want. New games will automatically sign in as well.
Google says this should mostly be transparent to the end user but does list a few potential issues for developers, but even those instances should be rare.
Source: Android Developers Blog