Android – how do you do this so that you can log in using the application’s phone number?

I'm making an application. I want to know the whole application so that you can log in with your phone number. For example, in the application down down lunch (an application that invites your friends to eat), the first thing you have to do after downloading is to log in with your phone number. Since then, Your phone number is your identification method in the application. What I want to know is whether the number will be added to the database table once the number is submitted? Then, when a new user registers, the number must be verified and checked against each number in the table to ensure that it is different? If so, won't it take a long time for a large user base (such as social networks), or just what can the database do? (more specifically, Amazon Web services, because I think I will use their relational database services)

resolvent:

You can use a library called digits, which is available on fabric

Please refer to the following links:

DIGITS – Sign in with Phone Number How to configure to app