If you want to add additional data, you need to create a model class for your user and then store it in your Firebase database . In general, after sign up, you can create a node tree for user like picture. Then, you can get the info with user key that can get by calling FirebaseUser.
Read moreWhat is custom authentication in Firebase?
You can integrate Firebase Authentication with a custom authentication system by modifying your authentication server to produce custom signed tokens when a user successfully signs in . Your app receives this token and uses it to authenticate with Firebase.
Read moreHow do I set Firebase authentication?
Get Started with Firebase Authentication on Websites
Read moreDoes firestore need backend?
The first thing that we need to know about a Firestore, is that most of the backend logic needs to be implemented on Front-end . For example, in our app, we need to send a message to another user or a group of users. In addition to this, it is necessary to change unread messages count and send a push notification.
Read moreHow do you make a Firebase backend?
store files in the Firebase Storage. create and host a web app with Firebase Hosting.
Read moreHow does Firebase authentication work?
How Authentication Works?
Read moreWhat authentication does Firebase use?
Firebase Authentication provides backend services, easy-to-use SDKs, and ready-made UI libraries to authenticate users to your app. It supports authentication using passwords, phone numbers, popular federated identity providers like Google, Facebook and Twitter, and more .
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