Android App Development -- 2

I'm looking for an experienced Android developer to create a comprehensive e-commerce application. The app should have the following key features:

User authentication
Push notifications
In-app purchases

Ideal Skills and Experience:
- Proven experience in developing e-commerce Android apps
- Strong knowledge of user authentication and secure payment systems
- Expertise in implementing push notifications
- Familiarity with in-app purchase integration
- Ability to design a user-friendly and engaging interface

Please share your portfolio and relevant experience.