Twitter-Based Audience Monitoring App – Ospriet
Ospriet is an open source web application, built by Twitter, that enables audiences to post and vote on questions/comments for talks, presentations, events, etc.
The application works with a dedicated Twitter account and anyone can send a question/comment by simply posting a @-reply to that account.
This tweet is then retweeted by Ospriet so that other users can see/favorite it and they will be presented as a list of most favorited entries in Ospriet's front-end.
It is built with Node.js, uses MongoDB for storing the data and uses Twitter's Bootstrap for the interface (which is responsive).