To qualify in this category an app must comply with certain high standards. “Attention to detail makes an app truly beautiful: transitions are fast and clear, layout and typography are crisp and meaningful, and design touches that delight you in surprising ways are sprinkled throughout,” Google explains.
Some of the apps to grab a place in the ‘beautiful’ ranking are familiar, and others you might not have heard of. They are all right below.
source: Android Developers