T-Mobile has gone all official and announced the launch of the MDA Vario IV in the UK.

The latest addition to T-Mobile's MDA range, the Vario IV is described as the HTC Touch Diamond but with a sliding QWERTY keyboard.

The Vario IV's full touch-screen slides out to reveal aforementioned QWERTY keyboard, meaning in theory using the applications like Microsoft Outlook, Word and PowerPoint on the move should be more productive.

The device also offers a 3.2-megapixel camera with autofocus, Wi-Fi, Bluetooth, high-speed web browsing via HSDPA and T-Mobile Web'n'walk and video and music players.

There's also in-built GPS, Google Maps and a new 3D user interface.

The MDA Vario IV will be available from T-Mobile stores from Summer 2008, pricing TBC.