Android Chatting App Development on React Native

I'm seeking a talented developer to create a chatting app using React Native, specifically for the Android platform.

Key Features:
- The app should support text messaging.
- It should also facilitate voice and video calls.

User Authentication:
- Implement a secure user sign-in system via email and password.

Ideal Skills and Experience:
- Proficiency in React Native.
- Prior experience in developing chatting applications is a plus.
- Expertise in implementing voice and video call features.
- Strong understanding of secure user authentication systems.