I can't figure out how to customize GKGameSession message notifications, if it's even possible. The default notifications do include a snippet of text that I supply when sending the message, but the result is awkwardly worded, uses the Game Center icon instead of my app's icon, and plays an annoying little jingle.
Ideally, I'd like to modify GKGameSession message notifications with a Notification Content Extension, but when I created one in my app, it was not invoked.
Any ideas? Thanks.