"With the work we have done with Nokia, HTC, Samsung and others ... there is now an opportunity to create really a strong third participant in the smartphone market," Ballmer said Monday, during a Windows Phone 8 launch event in Tel Aviv, Israel.
"We are still relatively small ... I expect the volumes on Windows Phone to really ramp quickly," said Ballmer, according to Reuters.
Microsoft formally launched Windows Phone 8 at an event last week in San Francisco. It's expected the devices will hit stores starting next week.
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Among the more anticipated Windows Phone 8 smartphones are the Nokia Lumia 920, which features optical image stabilization; the HTC Windows Phone 8X, which comes with Beats Audio; and the Samsung ATIV S. At 4.8 inches, the latter is the largest Windows Phone device on the market.
Despite generally positive reviews, Windows Phone-based devices have to date had little commercial success. According to the latest numbers from ComScore, Microsoft held just 3.6% of the smartphone OS market in September, down from 3.8% in June. Google's Android OS led the pack, with a share of 52.5%, while Apple's iPhone commanded a share of 34.3%. RIM's stake fell to 8.4%, from 10.7%.
Windows Phone 8's fate will be particularly crucial to Nokia, which has ported its entire smartphone line to the Microsoft platform. It was a risky but necessary bet, Nokia CEO Stephen Elop said recently. "We recognized that the industry had shifted," said Elop, at a launch event in New York City in September. "It had shifted from a battle of devices to a war of ecosystems."
Elop said Nokia joined forces with Microsoft because it needed a partner in its battle against Android and the iPhone. "In order to deliver to consumers a competitive experience, Nokia needed to be part of an ecosystem," he said.
In Tel Aviv Monday, Ballmer said the launch of the Windows 8 PC and tablet operating system last week would also help drive Windows Phone 8 sales, as both platforms offer a common user experience.
"The initial reaction to these products has been really, really phenomenal ... And if you look at how people will get Windows 8, the truth of the matter is more people over time will get Windows 8 by buying a new computer than by upgrading old computers," Ballmer said.
Microsoft shares were down 0.27%, to $29.42, in morning trading Monday.