Microsoft is releasing Xbox SmartGlass apps this week for "Game of Thrones," ahead of the Season 3 premiere March 31, reports Multichannel News. The feature works with the HBO Go service on an Xbox, available on iPad and Windows 8 tablets. Only U.S. Xbox owners who subscribe to HBO from a provider that offers HBO Go and also have an Xbox Live Gold subscription can get the app. Synchronized with the playback on TV, the SmartGlass tablet app functions as a companion guide to provide exclusive content.