A central Shelf: Loans and holds from all your libraries are automatically added to your Shelf.Libby offers many unique features and options that are not available in the OverDrive app. Libby, on the other hand, continues to have new features and updates added based on reader and librarian feedback. We are planning to discontinue the OverDrive app in early 2023. I do this on my kindle (long press on the book cover), so you don’t need PC for it.The OverDrive app is no longer under active development, meaning that we won't be adding new features or updates. Then I return the amazon copy as soon as I’m done reading so that I don’t get “your loan is about to expire” emails repeatedly. I personally use Libby on my phone and have started returning loans as soon as I have it downloaded on my kindle, so that it can move on to the next person waiting.

Even after that the cover stays on your kindle until you go to Amazon to delete it.

If you don’t return the book on kindle/Amazon, it’ll stay on your kindle until the loan expires. You can return the book on Libby as soon as you download the Amazon copy, you’ll still have access until the loan period ends, even if you no longer have it borrowed on Libby. The consequences of this system are that: You need to return the book to your library via Libby, but you also need to return the book to Amazon via your kindle/Amazon account for the copy to be removed from your kindle.

From there on Libby and Amazon/kindle are kind of divorced from each other. What happens when you send a book from Libby to kindle is that it downloads an Amazon copy and creates a loan on your Amazon account. You don’t need your computer but you can’t return a book to Libby via your kindle, if that makes sense. Sorry for the long response, the TL DR: No, you don’t need your PC.

Libby on kindle