Android Voice Chat Room App

I need an Android application that allows people to join real-time voice chat rooms, exchange short voice messages, and build public or private groups around shared interests. Every user should have a rich profile (avatar, bio, follower count, etc.) that is visible inside and outside rooms.

Access & security
Sign-in must happen exclusively through Gmail-based email login, using Google OAuth so the flow stays familiar and frictionless. No phone or other social options are required at launch, though the architecture should leave room for them later.

Core feature set
• Live group voice chat rooms with push-to-talk and host-controlled mic permissions
• One-to-one or one-to-many voice messages that can be played back inside the room or in direct chats
• Persistent user profiles that travel with the account across all rooms
• “SVIP” premium tier: higher room‐joining limits, priority mic access, and a distinctive badge
• “Seller” role: ability for approved users to flag a room as paid or to list digital goods/services directly in their profile (payment gateway integration can be stubbed for now)

Tech expectations
Develop in Android Studio with Kotlin (preferred) or Java, using clean MVVM architecture, Firebase or a similarly scalable real-time backend, and WebRTC or Agora for low-latency voice. Please include all project source, documented APIs, and a short setup guide so my in-house team can compile and test.

Acceptance criteria
1. App installs and runs without crashes on Android 10+.
2. Gmail login completes on first attempt and returns the correct user token.
3. Voice latency inside a room stays under 300 ms on a standard 4G connection.
4. SVIP badge and seller tag appear instantly after role change in the backend.
5. Play Store-ready build and code hand-off delivered through Git.

If something in the flow feels unclear, bring your suggestions—I’m happy to refine details early so development stays smooth.