Library is a small application that allows you to record the books you own, the ones you want to acquire and the ones you borrow from the library. It also allows you to add a comment to each book, a note, as well as the place where it is (or to whom it has been lent).
The application is free and open-source. It is distributed under the GPL-3.0 license. You can find the source code (and the code libraries used) on the Github repository :
The data that allows to find the books and their information comes from the Google Books web service. Although Library saves the books on your phone, you must be connected to the internet to fetch new books.