Nokia set to out three Windows Phone 7 handsets

Nokia looks is expected to launch three Windows Phone 7.5 Mango smartphones tomorrow at an event in London.

The new smartphones will be the first Windows Phone-based devices from the Finnish mobile giant since CEO Stephen Elop signed a deal to develop handsets for Microsoft's mobile operating system. Once the largest smartphone manufacturer in the world, Nokia has lost market share due to competition from Apple's iPhone and Android-based devices.

According to reports, the three handsets due to be unveiled will be the Nokia 800, Ace and Sabre - photos of which were leaked online last week. It appears Nokia won't be competing with large-screened WP7 handsets such as HTC's Titan. Instead, the Nokia 800 is reported to have a 3.7in screen, with the Sabre's display coming in at 3.5in.

Both the 800 and Ace are expected to have 8-megapixel cameras, whereas the cheaper Sabre could carry a 5MP camera. It's unclear whether the devices will boast single- or dual-core processors.

Nokia has so far failed to reveal any details about the handsets or the launch, but let slip that 'volume' shipments are not yet planned, and US might not see the launch of any devices this year. The handsets could be available in Europe by mid-November.

With Apple's iPhone 4S, Samsung's Galaxy Nexus and Motorola Razr already out there or in the process of being launched, Nokia will have a fierce battle at hand.