Cross-Platform Health App Development

I need an experienced developer to create a health-based app for both iOS and Android platforms. The app will utilize an existing SDK and API that I will provide.

Key Features:
- Monitor vital signs

Ideal Skills and Experience:
- Proficiency in mobile app development for both iOS and Android
- Experience integrating SDKs and APIs
- Strong background in health-related applications
- Knowledge of vital signs monitoring technologies
- UI/UX design skills for a user-friendly experience

Please share your portfolio and relevant experience.