services (realtime database, auth, hosting) of Firebase, Inc. platform • Provides backend services, easy-to-use SDKs, and ready-made UI libraries to authenticate users to your app* • Supports authentication using passwords, phone numbers, popular federated identity providers like Google, Facebook and Twitter, and more* * taken from https://firebase.google.com/docs/auth
implementation ‘com.google.android.gms:play-services-needed-service:9.4.0’* Where needed-service can be: "gcm", "location", “maps”, "ads" etc., play services implicitly includes firebase.
it’s phenomenally! • Custom Themes - customize the look of FirebaseUI to match your app. Also, because FirebaseUI is open source, you can fork the project and customize it exactly to your needs.