Because we read in an F shape, it can take a while to identify that you've already read or shelved a specific book you're looking at.

I found the Kindle development that shows read books as a banner on the image of the book as a very nice and useful visual cue to indicate you've already had interactions with that book.

Ideally, it the banner should display the exclusive shelf that the book is on, so that if we end up having more exclusive shelves further down the line, it wouldn't need to be adjusted.

This should apply to all images of a book, regardless of where they are shown across the site & app, so that it's always easy to identify a book that's already on one's radar (e.g. giveaways, or popular this week for example).