Hi I am commuting across 2 trains to get to my university and it is a burden to carry heavy textbooks. Is it at all possible to get ebooks to work on the iPad? I know the nook e-reader requires you to use their program which is not available on the iPad. So i guess i need to find a database that has an app for the iPad, or an e-book distributor that lets you download PDF files. Any ideas? Thanks.