Implement Yearly Subscription in Android App

I need an experienced developer to implement a yearly subscription for my Android app using Google In-App Purchase. The subscription needs to have auto-renewal functionality.

Key Tasks:
- Implement a fully integrated user interface for managing subscription options within the app.
- Use basic sketches I have to create the interface.

Ideal Skills and Experience:
- Proven experience with Android app development and Google In-App Purchase implementation.
- UI/UX design skills to interpret and enhance basic sketches into a user-friendly interface.
- Attention to detail to ensure a seamless integration of the subscription service.

Please only bid if you are 100% confident in your ability to deliver this project successfully.