Microsoft has announced plans to acquire Danger, the designer of the Sidekick mobile handset.

Robbie Bach, president of the Entertainment and Devices Division at Microsoft, said that the purchase "strengthens our dedication to improving mobile experiences centred around individuals and what they like".

He added that Danger has focused on a young, enthusiastic, internet-savvy and socially-inclined customer base by providing real-time mobile messaging, social networking and other applications.

Danger-powered handsets offer HTML web browsing, instant messaging, games, multimedia, social networking, web email and personal information management applications.

Microsoft hopes to combine these services with its own connected entertainment systems, including MSN, Xbox, Zune, Windows Live and Windows Mobile, to create a complete entertainment and communication platform for customers.

Danger was founded in 2000 by Andy Rubin, who went on to start Android which was acquired by Google in 2005, and is now shaping up to become a major rival to Windows Mobile.

Danger will become a part of Microsoft's entertainment and devices division. Terms of the purchase were not disclosed.