Live Voice Chat Android App

I want to develop a Live Voice Chat Android App similar to Hoob with smooth UI and real-time performance.

IMPORTANT:
The app must be fully functional and testable on my side before any milestone release.

Core Requirements:
- Real-time voice chat rooms (low latency)
- Public rooms (open for all users)
- Private rooms (invite-only)
- Topic-based rooms (categories)

Authentication:
- Email & password
- Phone number OTP
- Google login
Facebook login

Backend:
- Firebase integration (Authentication + Realtime Database/Firestore)
- All user actions must reflect instantly in Firebase

Testing & Verification (STRICT):
- Developer must provide LIVE testing proof
- Screen recording must include:
- Current date & time
- Real device testing (not old recording)
- Full app flow (login → room join → data update in Firebase)
- I will also test APK on my Android device

NOTE:
- No fake or old recordings will be accepted
- Payment will be released only after proper verification

I am looking for a serious and long-term developer.