Amazon has just pushed a new revision of its Kindle app to the iTunes App Store, and iPad owners will definitely want to hit that update button. That's because they now have access to the same full-color magazines and newspapers offered on the Kindle Fire, with both individual issues and subscriptions available. Amazon has also brought replica textbooks to the platform, with built-in support for annotation and zoom and pan functionality. New features extend to the iPhone and iPod Touch as well, with Send-to-Kindle email addresses now automatically syncing content to those devices. Further, PDF support has been added, allowing links in Mail and Safari to be viewed within the Kindle app. Finally, the library UI has been updated with improved organization.