Mobile App Development Full-Stack

Hi, I need someone who can help with a mobile app in React Native.

*All UI prototypes will be given.
*We have two programmers who will be working with you.

1. Build a chat system:
Allows users to communicate with each other;
Voice call and facetime call;
Group chat;
Allow users to create channels in a group chat;
2. Backend/Data development, including:
familiarity with SQL-like databases and MS Azure services;
APIs allow data transfer between databases;
cache data on the user's end;
Secure data on the user's end;

*Development period will be 1 month at maximum.
*US time zone is preferred.
*We will support you on coding as well.