** FireBasePhoneAuth **
Sample app to show the how phone authentication work using firebase. we can use firebase phone number verification by otp otp is send by firebase and it auto detect the sms and verify the phone number. some time auto detect not work then we can insert the otp code manually. if we din't get sms then we can request again to get the otp.
don't forget to add your google-service.json file without that app will not work.