I have an olde Barnes and Noble Nook that I rooted and installed Play Books. Used that for years to read public domain books that I got from Gutenberg and uploaded to Play to get position synced between my phone and Nook. Now I mostly read Libby. I also have the Kindle app on the Nook, so I need to see if the old version of the app still works and if I can send books from Libby to it.