For all you iPad, iPhone, and iPod users, Upload is available via iBookstore. Click here to view information about the eBook and purchase it through iTunes: http://itunes.apple.com/us/book/isbn9781300206705. You should also be able to download it directly to your iOS device. At the time of this post, here are the latest instructions from Apple:
iBooks includes the iBookstore. Tap the iBooks icon and your bookshelf appears. In the upper corner, tap the Store button and the bookshelf flips around to reveal the iBookstore. From the iBookstore, you can browse books by title, author, or genre. You can also view featured books as well as books available on the New York Times bestseller lists (United States only). Tap on a book to see more details and download a free sample. When you buy a book, it will automatically appear on your iBooks bookshelf.