Microsoft made available for download on June 21 the software development kit (SDK) for its recently announced SmartGlass Xbox companion application.
The SmartGlass SDK is available to "partners that have agreements to develop Xbox games or entertainment applications for the Xbox 360 console," a Microsoft spokesperson said. It also appears to be available to Microsoft employees.The SDK is downloadable here.
The SDK includes Xbox SmartGlass Studio for building SmartGlass "activities"; a JavaScript library, which includes "a set of device APIs that are consistent across all platforms"; and sample code.
Microsoft's press release on SmartGlass noted that it will be available "with select games and Xbox Live content and requires Internet connectivity and compatible devices." Xbox Live Gold membership will be required for some Xbox SmartGlass-enabled content and features.
SmartGlass is not available now; Microsoft officials are saying "later this year," which seems to imply there may be an Xbox Live Dashboard update required to make this work.