One area I've noticed the digital-world restriction is in reading sample chapter(s) in a Kindle book. If you decide to purchase the e-book at after finishing th

One area I've noticed the digital-world restriction is in reading sample chapter(s) in a Kindle book. If you decide to purchase the e-book at after finishing the sample chapter(s) the Kindle App does not offer a one-click `buy this book and keep reading` button. Presumably because of Apple's TOS and restrictions on in-app purchases. Instead the flow is to leave the kindle app, and find the book on Amazon's website in the browser and then purchase it there. Then return to the Kindle app refresh it and then switch to the new book.