I've been an ios/mac os app developer for the past 2 years and have worked with technology giants like Apple. I can start giving a shape to the app as soon as I hear the requirements.
The app as I picturize would ideally have a button to start shooting the scene which gives a clap and displays " Take 1" and starts the video capture, and when done, lets the video be played and gives the user option to do a "Take 2" and so on.
Please contact me for further analysis on the project.