J.J. Gadd, author of a 5-book series that uses some interactivity, muses on how authors can approach enhanced e-books.
In addition to her plug for engaging experts in book-making, I appreciated her mentioning the differences in various reading devices.
Authors and e-book developers should consider upfront where they will distribute their books. If they want to go wide and sell to Amazon, Kobo, Barnes & Noble, Google, Apple, etc.,, they must consider how various devices in each family utilize interactive features.
But if their aim is to make a highly interactive book (not just with hyperlinks, but with audio/video, fill-in-the-blanks, quiz-taking), then they need to understand that these books will only be makable and sellable on a few platforms.
From Digital Book World: