Open Audiobooks and E-books is the most popular free books app in the Play Store.

Open Audiobooks is an app that allows you to read and listen to audiobooks in a completely free and ad-supported way. There are thousands of books from classic authors that you can choose to read or listen to.

You can access the books for your Android tablet or mobile device. You can also listen to audiobooks in the background. This means you can read and listen to books and audiobooks without having to stop doing anything else.

You can also find many categories of books that will interest you, like horror, science fiction, thriller, fantasy, and many more.