Unity Ads is a monetisation tool for your game. It is a mobile advertising network that delivers market leading earnings. How? Our network only shows game video ads to gamers, meaning they’re far more relevant. That’s great for advertisers looking to drive downloads of their game and great for publishers looking to generate income from free to play games by selling advertising inventory.
Because your players only see ads for other games, they’re more valuable to advertisers; this way we can offer you the highest eCPM and fill rates. Choose to show interstitial ads between levels or engage your users by rewarding them for watching ads – either way your players remain engaged and happy.
See http://blogs.unity3d.com/2015/02/02/ads-monetization-overview for more information about game advertising and best practices for integrating ads into your game.
Unity Ads currently supports only iOS & Android.
If you are using Unity 5.1 (or earlier) or are integrating the Unity Ads Asset Store package, please see http://unityads.unity3d.com/help/monetization/unity-asset-package