How to sync non-Amazon ebooks across multiple Kindles and apps

Welcome to TNW Basics, a collection of tips, tricks, guides, and advice on how to easily get the most out of your gadgets, apps, and other stuff. One of the best parts of buying an ebook from Amazon is the syncing. You can read on your Kindle Paperwhite, then open the Kindle app on your phone and pick-up exactly where you left off. It’s what digital reading should be all about. I thought this synchronization was only possible with ebooks you actually bought from the Kindle store