Mac OS X gained share last month by the largest amount since March 2010, while iOS, the operating system that powers the iPhone and iPad, passed 2% for the first time, a Web metrics vendor said Tuesday.
January data from Net Applications put Mac OS's share up a quarter point to 5.25%, Apple's highest mark since last May.
iOS, meanwhile, grew by three-tenths of a point to 2.1%, a record for the iPhone and iPad operating system and double its share of July.
Android's January share was a half point, said Vince Vizzaccaro, vice president of marketing for Net Applications, who attributed a large part of the iOS advantage to the iPad's popularity. "A lot of iOS' growth has to do with the iPad," said Vizzaccaro, opining that tablets, not smartphones, are driving the browser usage of Apple's products.
That gibes with Android's poor showing compared to iOS, Vizzaccaro continued, because Android-based tablets remain rare. Later this year, as tablets running Android 3.0, aka Honeycomb, hit the streets, Google's operating system should show strong growth, he added.
"Android's bound to make an impact then," said Vizzaccaro, "although even then I don't see anyone knocking out the iPad for the foreseeable future. The iPad just has the 'cool' factor."
Net Applications measures operating system usage share by tabulating data acquired from the 160 million unique visitors who browse approximately 40,000 Web sites it monitors for clients.
Even with its gains last month, Apple's software was outnumbered more than 12-to-1 online by Microsoft's Windows, which remained the world's dominant OS by a huge margin.
Windows' share dropped under 90% for the first time in Net Applications tracking, losing six-tenths of a percentage point to close last month at 89.7%. January's decline was also a record for Windows, according to the metrics company's data.
But Vizzaccaro cautioned against reading too much in Windows falling below 90%. "Windows may have slipped under 90% for the first time, but if I'm Apple, I would love to have that 90%," said Vizzaccaro. "Is under 90% that big a deal? I don't think so."
Among the Windows editions Microsoft still supports, XP again fell the farthest, losing 1.5 points to end the month with a 55.3% share. Meanwhile, Vista lost just half a point to 11.7%.
Microsoft has been urging XP users to dump the aged OS for Windows 7, and Net Applications' data suggests that the message has hit home: Over the last three months, XP has dropped 3.7 percentage points, more than any one quarter in 2010.
Even so, it's likely that XP will remain on PCs for years to come. Net Applications' newest data indicated that if Windows XP continues to lose share at the average pace of the last three months, it won't dip under 50% until July 2011, and will still account for a quarter of all OSes in early 2013.
Windows 7 has benefitted from XP's decline.
Microsoft's newest operating system added 1.5 points to its share last month, ending January at 22.1%. If its current adoption rate continues, Windows 7 should have a 40% share by this time next year.
Last week during a quarterly earnings call, Microsoft executives boasted that the company has sold more than 300 million Windows 7 licenses since the October 2009 launch. Revenues for the Windows division were nearly flat, as PC sales have slowed dramatically.
Vizzaccaro noted that while Windows PC sales have lost the momentum they had in 2009 and early 2010 -- when Windows 7's debut was driving purchases -- Apple has logged several record quarters of Mac, iPhone and iPad sales.
"The increase in Mac OS and iOS coincides with Apple's sales," said Vizzaccaro. And the growth of both show that fears of iPad and iPhone cannibalization of Mac desktops and laptops may be unfounded.
"Clearly, iOS and Mac OS can co-exist," said Vizzaccaro.
Net Applications' January operating system data is available on its site.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed . His e-mail address is gkeizer@computerworld.com .
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