Microsoft chief Steve Ballmer on Tuesday unveiled his company's line of Windows smartphones in an offensive against Apple's iPhone and Google's Android system.
Around 30 types of "Windows phones" with various designs will be available by the end of the year in more than 20 countries.
Seven phone-makers, including Sony, Samsung and Toshiba, and 16 operators including Orange, Vodafone and T-Mobile, are involved in the launch.
The phones, which combine the ability to make calls, surf the Internet and view videos, carry Microsoft's Windows Mobile 6.5 operating system.
"We have done a lot of work on the user interface, we simplified the user interface," Ballmer told a news conference at Microsoft's new French headquarters near Paris in Issy-les-Moulineaux.
"We have taken the Internet Explorer browser technologies, and we rebuilt them for the first time for these Windows phones. So you can get the same experience on these phones that you will get on your windows PC," he said.
The new mobile operating system was launched simultaneously in France and New York on Tuesday.
With Tuesday's launch Microsoft hopes to reassert itself on the smartphone market, where it has lost ground. The sector is considered especially promising, with 29 percent jump in sales expected this year.
But in the second quarter only 9.0 percent of all smartphones sold were equipped with Microsoft's operating system, against 12 percent a year earlier, according to the Gartner research group.
At the same time, Apple's iPhone has seen its share jump from 2.8 to 13.3 percent.
Google, which launched its Android system in early 2008 and is provided free to phone-makers, managed to secure a share of almost 2.0 percent in a few months and could gain further ground in the fourth quarter this year.
(c) 2009 AFP
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