title: Replace firebase phone authentication with sms retriever api for otp verification
body: <p>so I'm new to android development (which doesn't mean that I don't understand other people's code, just hands-on experience wise) and currently working on an android app. The app was made by the previous person who left the job for which I was recently hired. The problem is, since Google has updated their policies not allowing us to use permissions such as READ_SMS and RECEIVE_SMS, the app that the previous person made, is not being approved by Google for uploading to the play store.</p>
  
  <p>My question, is there any way by which I can either replace firebase authentication with SMS retriever API but using firebase at the end? Or is there any other way by which I can authenticate the user based on the OTP sent by firebase but without permissions for RECEIVE_SMS or READ_SMS??</p>
  
  <p>Currently, I've checked out SMS Retriever and seems fit for our app, but don't know if we can still go on to use firebase.</p>