The Educreations iPad app is a free download in the App Store which transforms the tablet into an interactive whiteboard. It will record a teacher’s voice and handwriting as they teach. Teachers can add photos to their lessons from the Photo Library or camera (iPad2), or a Dropbox account. Animation is possible by tapping and dragging.
A teacher can then link to the lesson via educreations.com. These can be shared privately or to the world.
I believe this could be the ultimate for all the "IWB" - iPad hacks teachers have been using. Great job, Educreations.