Hi Friends. In this tutorial, we will learn how to implement firebase phone authentication with it's origin. Digits is an Simple User Phone Authentication Service to create easy login experience. Now Digits is acquired by Google's Firebase and it provides free service for limited amount of authentication per month. However, if you need to sign in a very high volume of users with phone authentication, you might need to upgrade your pricing plan. See the pricing page. You can use Firebase Authentication to sign in a user by sending an SMS message to the user's phone. The user signs in using a one-time code contained in the SMS message. Setup Firebase To setup firebase in your project, read previous post . After setting up, open Authentication sign in method and enable phone authentication method. You should Add SHA Fingerprint in your application. To get SHA Fingerprint use the following Code with Command Prompt in Windows keytool -list -v -keystore "%USERPROFILE%\.and...