Microsoft has made available the software development kit for its forthcoming Xbox SmartGlass companion app. The SDK will help partners add SmartGlass functionality to their Xbox 360 games and applications.

Xbox SmartGlass will be coming to iOS, Android, Windows 8 and Windows Phone platforms in this autumn, and allows users to interact with their Xbox 360 consoles in all-new ways.

Announced at E3 in LA at the beginning of June, Microsoft demonstrated the new application to Pocket-lint during a behind-closed-doors session and we were treated to a look at some of its potential. We saw the companion application work with an episode of Game of Thrones, where SmartGlass offered more information and details as the show was running.

Similarly, the film School of Rock could be accessed through the tablet software, with extended bonus material accessible on the second screen as it streams through the console.

And forthcoming Xbox Live game Ascend offers an interactive map on a mobile device so that players can see where they are going without having to pull up an in-game menu.

These are just a few of the features Xbox SmartGlass can offer, but we suspect that now the SDK is available, developers will be discovering plenty of other ways to use companion services.

Registered Xbox 360 developers and Microsoft partners can download the package from Xbox.com's developer-only section.

Are you looking forward to Xbox SmartGlass? Will it eventually be as useful as the Wii U GamePad? Let us know in the comments below...