A couple of months ago, Kno announced that they where getting out of the hardware business to concentrate of mobile device apps for textbooks. It was a bit disappointing because they had a very interesting dual screen full-color concept that would have worked well as a paper-based textbook alternative.
Today, they have announced the beta release of their iPad app. Not being an iPad owner myself, I invite you to get free the app and test it out. They offer a free textbook as an incentive.