Today is the first day in which Windows 8 is available, and as noted a few days ago, Smart Glass is also part of the package. Provided one has a Windows 8 tablet, like Microsoft's very Surface.
As also explained previously, it's an app that is designed to augment the game playing experience for Xbox 360 titles by acting like a secondary screen or offering an alternative control method, depending on the title.
If it sounds a lot like what the WiiU GamePad is designed to do, then it should.
Many were expecting that Smart Glass would a killer app for the Surface, but it just popped up on the Google Play store and is now available for use on a variety of Android devices.
This is certainly a surprise development. Especially since it was assumed that the first smart phone version would hit Window Phone 8 Phone, due this upcoming Monday.
No word yet on an iOS version, but at this rate, it might be coming much sooner than expected.