This move provides greater choice to Firebase customers — until now, it was only possible to send push notifications through Android and iOS apps with Firebase Cloud Messaging (and before that ...

App developers deliver push notifications using Apple’s Push Notification Service on iOS or Google’s Firebase Cloud Messaging on Android.

On iOS, most developers tend to use Apple Push Notification Service (APNs). For Android specialists, the API of choice is Google’s Firebase Cloud Messaging (FCM).

The service uses Google's Firebase Service to send notifications to your Android phone when new iMessages arrive. Check this dedicated guide if you are interested in using BlueBubbles.