Android App Backend Development

I need an experienced backend developer to support an Android app. The backend should be robust, secure, and scalable.

Key Requirements:
- User Authentication: Implement secure login/signup features.
- Database Management: Efficiently manage user data and app content.
- API Integration: Connect with third-party services as needed.

Preferred Database: MySQL, but I'm open to suggestions.

Ideal Skills and Experience:
- Proven experience in backend development for mobile apps.
- Strong knowledge of MySQL and database management.
- Expertise in API integration.
- Familiarity with Android app requirements and security protocols.

Please share your portfolio and relevant experience.