Mac OS X 10.7 Lion will launch in July and will only be available through the Mac App Store, Apple has announced.

Boasting more than 250 new features, Mac OS X 10.7 Lion will be a 4GB download and will cost £20.99.

There are a whole host of new features in Mac OS X 10.7 Lion, including support for new Multi-Touch gestures such as momentum scrolling, tapping or pinching your fingers to zoom in on a web page or image, and swiping left or right to turn a page or switch between full screen apps.

There is support for full screen apps, meaning you can swipe from one window to another, between full screen apps, or back to your Desktop, Dashboard or Spaces without ever leaving full screen.

Also new to Lion is Mission Control, which provides and overview of everything running on your Mac, combining Exposé, full screen apps, Dashboard and Spaces into one unified experience.

The Mac App Store will be built in to the OS; Launchpad, a new home for all your apps where a single Multi-Touch gesture presents all your Mac apps in a full screen layout, is another new feature and there is a completely redesigned Mail app.

The new Conversations feature groups related messages into an scrollable timeline, hiding repeated text so the conversation is easy to follow, and retaining graphics and attachments as they were originally sent, Apple said.

"The Mac has outpaced the PC industry every quarter for five years running and with OS X Lion we plan to keep extending our lead," said Philip Schiller, Apple's senior vice president of Worldwide Product Marketing.

"The best version of OS X yet, Lion is packed with innovative features such as new Multi-Touch gestures, system-wide support for full screen apps, and Mission Control for instantly accessing everything running on your Mac."

Lion requires an Intel-based Mac with a Core 2 Duo, i3, i5, i7 or Xeon processor and 2GB of RAM. The Lion upgrade can be installed on all your authorised personal Macs.

Mac OS X Lion Server requires Lion and will be available in July from the Mac App Store for £34.99.