Google has pushed out a new version of Play Books with material design, but it's not just a different look. Version 3.2 might change the way you read books on your device. It certainly looks nicer, but you can also easily skim through a book with a flick.
The first things you'll notice are the use of the colored status bar, new animations, and a redesigned navigation menu. When you're reading a book, tapping in the center no longer just brings up an action bar. It now zooms out to show pages as a filmstrip that you can slide through. There's also the usual progress slider at the bottom to jump around. It's a neat interface.
The APK is signed by Google and upgrades your existing app. The cryptographic signature guarantees that the file is safe to install and was not tampered with in any way. Rather than wait for Google to push this download to your devices, which can take days, download and install it just like any other APK.
File name: com.google.android.apps.books-3.2.55-30255-minAPI14.apk.
Version: 3.2.55 (30255) (Android 4.0+).