Kindle App on my iPad keeps crashing

I have turned off my iPads. Nothing resolves this issue. How do I tell Amazon? They are still urging me to buy books for Kindle!

Hi. I click on the Kindle app, it comes on screen with my books illustrated and then it vanishes, leaving only my Home Screen in view. It has now been 3 days. I don’t want to delete the app and reinstall as I fear losing all my books. I have 2 iPads. This happens on them both. Any ideas?

[Re-Titled by Moderator]