You cannot buy books directly inside the Kindle iPad app because of Apple’s in-app purchase commissions.
While Apple’s ecosystem is the most seamless, it’s far from your only option. Here is everything you need to know about buying books for your iPad. 1. The Native Choice: Apple Books buy books for ipad
if you want the lowest prices and the biggest selection. Choose Libby if you’re a heavy reader on a budget. You cannot buy books directly inside the Kindle
Open Safari, go to the Amazon Kindle Store , purchase your book there, and it will automatically appear in your iPad's Kindle app. 3. The Best Alternatives: Kobo and Google Play go to the Amazon Kindle Store