The app allows attendees to ask questions (anonymously) about a presentation or lecture. The submitted questions are shown in real-time to all other attendees using the app. Attendees can cast votes for questions, which will produce a most-wanted list of questions the lecturer can address at the end of the presentation or lecture.
The 'Present!' mobile webapp is a submission for the winner of the Apps On (in Dutch) contest.
See it the prototype in action on http://present.nodejitsu.com.
It's available as Open Source under the MIT License.
Node.js (http://nodejs.org/)
MongoDB (http://www.mongodb.org/)