Hi,
I would cover design of the app from the mockups, the functions would be as follows.
1. Open the camera for recording video
2. Capture the video
3. After the capture is done, open the video in the player for adding audio or text at the particular length.
4. List of videos recorded, when you tap, the video will be played in the player.
5. Upload selected video to server.
6. Write upload API
I would cover this much, let me know if you have any query.
Thanks & Regards
Priyanka