Annotations you've added to books and content on a Kindle app/device.The function syncs the following content: Whispersync is an automatic feature built into Kindle apps across platforms, including on Kindle hardware itself. Start a book in the Kindle for iPhone app on your commute to work, pick it up in the OS X app at lunch and then finish off on your actual Kindle hardware in the evening. With the versatility of the Kindle platform, it's not out of the question that you'll want to read your content across devices. Kindle for Mac works fully with Whispersync and Send to Kindle, features of Amazon's Kindle ecosystem that we'll look at next.
