If you're going to do this, add the ability to retro-record (i.e. when you press the record button, the recording starts from 30 seconds in the past - meaning that you'd have to record continuously and have the 30 seconds on a cache at any given time).
Retro-record is a great way of putting it but I think a phone app doesn't really need retro-record even in this case. However, phone integration with lookxie (http://looxcie.com/) might be interesting.
