For my course on how to use Unity's new UI Tools go here:
https://www.udemy.com/learn-unitys-new-ui-tools/?couponCode=PE-YOUTUBE-pop2
Add Google Play Game Services to your Unity Game.
Supports:
Achievements
Leaderboards
Cloud storage
Realtime Multiplayer
Works with the Free version of Unity.
http://www.platoevolved.com/blog/unity-plugins/#!/~/product/category=2743024&id=24117117
