Kindle for ipad app won't open

There have been multiple threads posted lately on this. According to them, people have reached out to Kindle and Kindle has acknowledged an issue which they are working on. Only Kindle can fix their App as only Kindle owns the app and the code in the app. Bottom line, you'll need to wait until Kindle issues an app update to fix their app. Something they should be highly motivated to do as people can't buy books from an App which doesn't work.

Hey Icewynde,

Looks like the app should still work on iPadOS 12.0 or later. If the iPad is as updated as it can be, and you've uninstalled and reinstalled the app with the issue persisting, you may next want to reach out to the app developer since it's specific to their app. For more help, check out: If an app on your iPhone or iPad stops responding, closes unexpectedly, or won’t open - Apple Support

We hope they're able to help out further.

Take care!