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I recently bought a Kindle 4th/5th generation under the impression that I could sync reading position from Kindle device to Android Kindle app. I previously downloaded the book and used send to kindle email to send it to my phone. When I downloaded the book on the kindle device from the archives documents, the book opened on the same page as on Android. But when I read further on the Kindle device, it doesn’t show that I’ve read further when I open it up again on the android. I’ve tried turning on all the settings but it doesn’t work. How can I get it to sync both ways?