The new Xbox SmartGlass app is one of the new apps that is headlining Microsoft's efforts to tie all Microsoft and Windows devices together. In a nutshell, Xbox SmartGlass lets users use their phones or tablets to double up as a secondary display for their Xbox 360 consoles.
Just about a week ago, Microsoft introduced the Android version of the SmartGlass app, and now the iOS version is available for iPhones and iPads. Only a handful of games currently support SmartGlass, but expect the list to grow in time to come. Also, despite the iPhone 5 having been in the market for over a month now, the SmartGlass app isn't optimized for it and doesn't take up the iPhone 5's entire screen.