Currently available for iPhone, iPad, and BlackBerry, Amazon will soon release a Kindle app for the Android OS. It will include access to Amazon's library of over 500,000 books, plus a pretty attractive looking user interface and all the features of other apps. This does have one special feature though, which is the ability to buy books from the app instead of using iPhone's Safari web browser. As of now, Amazon only says it will be coming soon, but Android users can sign up for more updates on the free Kindle Android app here.