Amazon on Monday announced the release of Fire OS 3.1, which includes new features for its Kindle Fire HD and Kindle Fire HDX devices. You can download the free update now directly from here or get it over-the-air automatically “in the coming weeks.” First and foremost, Amazon has added Goodreads integration, which isn’t much of a surprise given the company’s acquisition of the social book site back in March. Amazon even teased Goodreads integration when it announced its new Kindle Paperwhite, so support for its other Kindle devices was definitely expected. Because Goodreads is now part of the reading experience, there’s no need to leave a book and open the Goodreads app. Kindle owners can directly share favorite quotes with Goodreads friends from inside books, see what friends are reading via the Goodreads updates feed, and more.