Riffiti

Riffiti is a new way of learning, where everyone learns from everyone. You open the app and it gives you a set of topics, or you can ask your own question. You pick a topic and record a short video on your phone explaining that concept or idea in 20 seconds in your own way. Others are doing the same on the same topic and everyone learns from this diverse set of responses.

Links:

http://riffiti.com