You may notice that all the books have locks on them. A lock means that you haven't purchased a digital copy of that book within this app. This is one of the pay features of the app, but this doesn't mean you still can't peruse some of the books' features. Tapping any of the books will allow you to "pull" it off the shelf. You'll then have the option to buy the book within the app, read an excerpt of the book, or return to the shelf. If you swipe to the left, you can scroll through all of the books on the shelf, and if you tap any of the book covers, it will turn over and reveal the book's synopsis.
Once you've purchased a book within the app, the lock on that book will disappear. So, if you're someone who prefers digital formats, this is a handy way to collect them. These app editions also have some cool features, which is what we'll talk about tomorrow. And as always, more questions and answers are addressed by clicking the "app" tab below, reading Penguin's FAQ, or emailing firstname.lastname@example.org.