firebase_messaging for Firebase Messaging (FCM)

flutter_firebase_ui for quick Firebase Auth integrations
(Facebook, Google, Twitter and email)

cloud_firestore for Firebase Cloud Firestore

You can also find some third-party Firebase plugins on pub.dev
that cover areas not directly covered by the first-party plugins.

How do I build my own custom native integrations?

If there is platform-specific functionality that Flutter
or its community plugins are missing,
you can build your own following the
developing packages and plugins page.

Flutter’s plugin architecture, in a nutshell,
is much like using an Event bus in Android:
you fire off a message and let the receiver process and emit a result
back to you. In this case, the receiver is code running on the native side
on Android or iOS.

Themes (Styles)

How do I theme my app?