Since you can’t buy Kindle books from the Kindle reader app for iPhone or iPad, try adding a shortcut to the Kindle store on your iOS home screen.
Compared: iPad mini vs Kindle Paperwhite
Has Found a Clever Way to Avoid Giving Apple a 30% Cut of
How to Delete Books from Kindle App or Device
You can now permanently delete Kindle books directly in your iPad
Kindle (2022 Release) Review
How Can I Add Widgets to my iPad Home Screen? - Ask Dave Taylor
The New Kindle Home Page Is Useless
How to Buy Kindle Books on iPhone & iPad
How to Buy Books on the Kindle App: 6 Easy Methods
The ultimate guide to using Kindle app for iPad and iPhone – Ebook
How Can I Add Widgets to my iPad Home Screen? - Ask Dave Taylor