Android App Development with OTP Login

I need an Android app developed that includes a user login feature. The login method should be via phone number OTP.

Requirements:
- Experience in Android app development
- Proficiency in implementing secure and reliable OTP login systems
- Knowledge of user authentication protocols

Ideal Skills:
- Android SDK
- Firebase or similar for OTP
- UI/UX design for user-friendly login interface

Please provide a portfolio of similar work. Looking forward to your bids!