The whole point of owning an Amazon tablet is that you're eventually gonna buy stuff. Want movies? Amazon's got you covered. Music? Time to check out Amazon's MP3 store. And then, of course, there's books: Amazon expects you to buy lots and lots of reading material through the built-in Kindle app. Now, though, another company is trying to get in on the action. Scribd, which already runs a $9-a-month e-book subscription service, is opening up shop on Kindle Fire tablets. As on the existing apps (Android, iOS and a web version), the Kindle version offers unlimited monthly access, allowing readers to share what they're reading and embed books onto websites. The catch? Scribd only has a deal with one major publishing house, HarperCollins, with the rest of the catalog comprised of titles from independent publishers. So, while you'll enjoy authors like Michael Chabon and classics like Sh*t My Dad Says, you'll be missing out on things like the Game of Thrones series. Then again, if you read even two books a month, that $9 fee could pay for itself.