I'm Developing an Android app and using Firebase as my Backend

Question

By Using Firebase , all my Logic will be inside the client app . So if someone got my source code by reverse engineering the android app , then he/she can easily change the Fi

Answer 1

If I understand you right, you are using firebase database. You shoud read how firebase security rules work. It is possible to let a user only access and modify his own data if the user is authenticated via one of Firebase auth's methods (you mentioned phone auth). As you haven't provide example code, I can't give you a concrete usage, but you can find many examples in the firebase docs about "Securing user data".

If you do it like this, it doesn't matter what a "hacker" would do as he needs to authenticate with another user's number first. (=impossible)

Answer 2

Just use Progaurd to obfuscate your code.You can find more on this link