Very good service, but with some quirks – Libby, by OverDrive Review

Libby allows you to “read” a book and have it on your shelf for long amounts of time, even when the hold requests made by other people pile up. People will often finish their books and not return them, so Libby will not automatically return the book for almost 21 days which is a long wait for the 3-4 people waiting for one book. Is it nice to have a library on your phone? Yes. But there aren’t as many copies of books for you to borrow, so may have to wait a very long time and the numbering books available is smaller than that of a real library
Review by BabyMay23 on Libby, by OverDrive.