Not only will retail Xbox Ones be able to transform into Universal Windows Platform (UWP) dev kits, it will also pick up access to tons of Windows 10 Universal Windows apps and games via an all-new unified store.

In order for developers to make use of the Universal Windows Platform, the Xbox One will need new features to ensure those API calls are present across all devices. As such, Cortana and background music are both finally making their way to the Xbox One as part of this summer's Windows 10 Anniversary Update. Phil Spencer said that more details on what the Anniversary Update means for Xbox One will arrive at this year's E3, while emphasising that UWP will continue to be a fully open ecosystem for game developers.

We were able to take a look at an early port of Cortana running on Xbox One late last year, you can check that video out over here. The final version is certain to be far more comprehensive, allowing you to easily find out if your friends are online, form parties, and more.

During the keynote, Spencer also demonstrated how Project Centennial allowed Win32 games Age of Empires II HD and The Witcher 3 to easily translate to UWP, and how UWP apps were designed to easily work with Xbox game controllers with minimal code changes.

The Anniversary Update will arrive for free this summer to all Windows 10 devices, including Xbox, and will further unify those devices under the Universal Windows Platform.

For all the latest and greatest from this year's Build conference, head over here.