Apple's upgrade to its Mac computer operating system will be available to buy from July, the company has revealed. OS X Mountain Lion will be the ninth release of the software and feature more than 200 new features.

Several of these new talents were announced by Apple at its WWDC 2012 event in San Francisco today, including Game Center support with cross-platform multiplayer gaming. This will allow certain players to compete against each other on iPhone, iPad or Mac. Scores and accounts will be interchangeable, too.

AirPlay Mirroring is also coming to OS X Mountain Lion. You will be able to stream up to 1080p video of what is on your screen to an Apple TV or AirPlay-compatible AV receivers.

Safari has had an overhaul too, and there was a new feature announced: Power Nap. This allows the new MacBook Pro and MacBook Air notebooks from second-generation and up to download updates, back themselves up or interact with several key applications, such as email, while the computer is in standby mode.

As with iOS 6, which was also announced, there will be Facebook integration throughout.

OS X Mountain Lion will be available as an upgrade in the Mac App Store from July for $19.99.