Now hold on...

Video based super micro blogging/messaging platform where users can post short form video.
If you like what you see just hold on, if not then let go and watch it rewind.

Super tactile interfcae where user interaction directly affects the video. The lifetime of a post is completely dependant on who and how many people watch each post until the end and how many people let go and leave it to rewind.

Whoever views a video post has complete control watching the video as long as they hold the screen, if they let go then the video rewinds, the user can begin playing the video again by retouching the screen - they only have a limited number of times they can do this before it rewinds on its own to the beginning and disappears completely - over the event horizon! or down the plughole!
If they do watch it to the end then they have a chance to save the video to their favourites.

There could be a time limit on how long they can keep each video or not? The user who posted the video is notified they have had a full view or how many full views each video has had.

They can also track each of their posts to see how many rewinds each one has had. Each video is categorised so can be easily discovered.