I suggest using UnifiedPush, the community successor to the OpenPush design. Although UnifiedPush is brand new, I'm not aware of any other app-independent implementation. The end-user experience is that they only have one notifications app to setup once, then any supporting app communicates with it to handle push notifications.
I believe the technical approach would be to use the "FCM-added" form of the UnifiedPush android-connector library so that users who don't care about the minimal FCM data can continue to use it as before. The only currently available UnifiedPush app is FluffyChat, implemented in lib/utils/firebase_controller.dart.
I suggest using UnifiedPush, the community successor to the OpenPush design. Although UnifiedPush is brand new, I'm not aware of any other app-independent implementation. The end-user experience is that they only have one notifications app to setup once, then any supporting app communicates with it to handle push notifications.
I believe the technical approach would be to use the "FCM-added" form of the UnifiedPush android-connector library so that users who don't care about the minimal FCM data can continue to use it as before. The only currently available UnifiedPush app is FluffyChat, implemented in lib/utils/firebase_controller.dart.