Android Business App Development

I'm looking for an experienced Android developer to create a business application. This app needs to incorporate the following key features:

- User Authentication: The app should have a secure login system using email and password.
- Credit Score : Clients check credit score.
- Chatbot: client write query in chatbot and company reply backend side.
- Calculator: mortgage loan calculate - Amount filling column, monthly interest/yearly, time duration,
- Payment Processing: The app will need to handle transactions smoothly and securely.
- Push Notifications: The app should be able to send timely updates and notifications to users.

Ideal Skills:
- Proficiency in Android SDK and Java/Kotlin.
- Experience with integrating secure user authentication systems.
- Prior work with payment gateway APIs.
- Knowledge in setting up push notification services.
- Familiarity with state management (Provider, Redux, MobX, etc.)
- Experience with mobile UI frameworks (Material Design, Cupertino, etc.)

If you are a dedicated professional with a proven track record in Android app development, I look forward to your proposal.