Microsoft set out to win over iPhone and Android gadget devotees with Windows 8 smartphones, new devices that emphasise individualism and unify digital lives in the Internet cloud.

Windows Phone 8 is the final component in Microsoft's new equation and shares a user interfaced based on "tiles" that can be personalised with people's pictures, applications, games, music and more.

Microsoft has partnered with Facebook to optimise a Windows 8 version of the social network's application that includes serving up slide shows of personal pictures to handset lock-screens.

A "live apps" feature allows for sports scores, messages, images or data to be streamed to an ever-changing lock-page on phones.

A Twitter application was also tailored with Windows 8.

Windows 8 smartphones will roll out around the world in November and December.