Chat & Voice App Development

I'm looking to create a chat and voice chat application targeting Indian male users. The app will allow users to create profiles and chat with female profiles (real or hosts). Unlock voice chat features through coins or subscriptions.

Key Features:
- User Registration
- Chat System
- Coin-Based Payment for Messages/Calls
- Voice Chat (using Agora or Twilio)
- Simple Admin Panel to Manage Users/Hosts
- Support for Razorpay and UPI for Indian Payments
- Available on Android

Ideal Skills and Experience:
- Mobile app development (Android)
- Experience with chat and voice integration (Agora/Twilio)
- Familiarity with Razorpay and UPI
- Backend development for admin panel and payment systems

Please suggest the best tech stack and estimated development time. I'm open to prebuilt code if it's cost-effective.