Amazon added a new font in this update called Bookerly. This new spacious font initially debuted on Amazon's Kindle Paperwhite before being deployed to the kindle family of devices. Bookerly is now available for Kindle apps, on Android and iOS.
Another feature that Amazon is porting to its Android app is Word Runner, "a fun new way to read faster." Enabling Word Runner will display the text in the middle of the page to keep "your eyes focused on the center of the page and brings each word right to where your eyes already are." This sounds cool and I will definitely give it a try and post my feedback later. Will you use Word Runner?
Download the free update on Google Play Store to try Word Runner and Bookerly.