Its partner Nokia also saw significant market erosion during the period. RIM was also hit hard, according to Gartner.
Samsung led the mobile hardware market, with a 20.7% share, while Google's Android OS was the top mobile OS, with a share of 56.1%. Apple, third in hardware with a share of 7.9%, was the second leading mobile OS developer, with iOS capturing 22.9% of the market, up from 16.9% year over year.
Microsoft and Nokia weren't alone in feeling the pinch, as worldwide mobile phone sales contracted 2% compared to the previous year. Gartner said it's the first time that the market experienced a quarterly decline since the second quarter of 2009.
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"Global sales of mobile devices declined more than expected due to a slowdown in demand in the Asia/Pacific region," said Gartner analyst Anshul Gupta, in a statement.
"The first quarter, traditionally the strongest quarter for Asia, which is driven by Chinese New Year, saw a lack of new product launches from leading manufacturers, and users delayed upgrades in the hope of better smartphone deals arriving this year."
Although the market was sluggish overall, it was mostly generic, "white box" manufacturers that saw declines. Microsoft and Nokia, along with Research In Motion--Blackberry OS's market share fell 47%, to 6.9%--were the only major market participants to see significant fall offs in share.
Microsoft introduced its Windows Phone OS in late 2010, and has since spent billions of dollars developing and marketing the platform. It's also paying Nokia billions to help the Finnish phone maker port its entire smartphone line to Windows Phone. To date, those moves aren't panning out.
Windows Phone's Metro interface, which offers a home screen divided into blocks called Live Tiles instead of the standard, icon-based GUI, has been well received by some critics. But others believe it's simply too much of a departure from what consumers, conditioned by the iPhone and Android, have come to expect from a mobile interface.
The first quarter numbers do not include sales of the flagship of the Windows Phone line, the Nokia Lumia 900. The Lumia 900, which offers high-end features such as Carl Zeiss camera optics, launched in April amid a high-profile marketing push that featured Nicki Minaj.
Analysts will watch closely to see if the Lumia is able to reverse Microsoft and Nokia's mobile slide in the second quarter. If not, some might conclude that Microsoft's Windows Phone gambit has failed.
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