…it’s a pity that Apple has chosen to re-enter the education market with a pitch about Reinventing the Textbook that, frankly, sounds pretty old hat. The reason, I suppose, is that there’s potentially a lot of money to be made selling the things to schools as replacements for the books.

Spaced repetition! "Designed to help you remember facts (such as words and phrases in a foreign language) as easily, quickly and efficiently as possible. To do this, it tracks how well you remember each fact, and uses that info to schedule review times.