Google Play Games plugin for Unity

http://picocurl.com/2IuC
https://github.com/playgameservices/play-games-plugin-for-unity/blob/master/README.md

Google Play Games plugin FOR Unity

Copyright (c) 2014 Google Inc. All rights reserved.

The Google Play Games plugin FOR Unity® is an open-source project whose goal is TO provide a plugin that allows game developers TO integrate WITH the Google Play Games API from a game written in Unity®. However, this project is NOT in any way endorsed OR supervised BY Unity Technologies.

Unity® is a trademark OF Unity Technologies.

iOS is a trademark OF Apple, Inc.

Overview

The Google Play Games plugin FOR Unity allows you TO access the Google Play Games API through Unity's social interface. The plugin provides support for the following features of the Google Play Games API:

sign in
unlock/reveal/increment achievement
post score to leaderboard
cloud save read/write
show built-in achievement/leaderboards UI
events and quests
nearby connections
turn-based multiplayer
real-time multiplayer
NOTICE: Google Play games services for iOS is deprecated, and is not likely to function as expected. Do not use Google Play games services for iOS in new apps. See the deprecation announcement blog post for more details.

Features:

easy GUI-oriented project setup (integrated into the Unity GUI)
cross-platform support (Android and iOS) with no need for platform glue code.
(Android) no need to override/customize the player Activity
(Android) no need to override/customize AndroidManifest.xml
(iOS) integrates into XCode build using Cocoapods to manage the framework dependencies.
System requirements:

Unity® 5 or above.

Note:4.6.8 works at runtime, but some editor functionality does not work. as a result, use of older version of Unity are at your own peril.

To deploy on Android:

Android SDK
Android v4.0 or higher
Google Play Services library, version 8.4 or above
To deploy on iOS:

XCode 6 or above
Cocoapods