The epub version is compatible with almost all ebook readers, including Apple iPad, Barnes and Noble Nook, Sony Reader, BeBook, Adobe Digital Editions, Lexcycle Stanza, BookGlutton, AZARDI, Aldiko, WordPlayer on Android, the Mozilla Firefox add-on OpenBerg Lector, Cool Reader (for Windows, Linux, Android) and more, but not the Kindles.
If you don't have a Kindle, and you don't plan to print out sections, this is probably the most easily readable version. If you don't have a reader installed on your tablet, just download the free Cool Reader.
You can download it instantly and then transfer it to your ebook reader. For the full list of compatible devices see this table. File size 36Mb