How to buy books on Kindle (and why you can't from the app)
You can buy books directly on your Kindle by accessing the Kindle Store and tapping the Buy button. You can also buy books ...
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Why You Can't Buy Books Through The Kindle Or Amazon Mobile Apps, Explained
You can now browse the Kindle Store and search for specific books. Once you've found a book you want, tap Buy now with 1-Click to buy it. If you want to buy a book you added to your Kindle list ...