Amazon today said that it'll release a Kindle app for Windows Phone 7 later this year. People can already read Kindle books on the iPad, iPod touch, iPhone, Macs, PCs, BlackBerrys, and Android-based devices (and sync their place in a book across the multiple gadgets).
Amazon said the Kindle for Windows Phone 7 will have some new features, including personalized book recommendations and the ability to send an "e-mail to a friend with a link to the book you're reading or to any book in your library without leaving the app."
It's increasingly clear that Amazon views Kindle as two businesses -- the device and the digital bookstore. Amazon CEO Jeff Bezos, the company's May shareholders meeting, talked about how each business will succeed on its own merits.
The Kindle bookstore is now up to 725,000 titles.