Apple's iPhone lost share among U.S. consumers who bought a mobile phone in the last three months, while the share for devices running Google's Android climbed, Nielsen said Monday.
In August, 28% of those who had purchased a smartphone in the preceding 90 days said that they picked an iPhone, down from 31% who said the same three months earlier.
Android's share of recent smartphone buyers jumped from 49% in May to 56% in August, according to Nielsen's data.
However, more of Android's gains came at the expense of Research in Motion's BlackBerry than from Apple's iPhone: RIM's share of recent smartphone purchases fell from 16% in May to 9% in August, a seven-point decline that was more than double that of Apple's.
"There's always flux in numbers like these," said Jack Gold, a telecommunications analyst at J. Gold Associates. "You can't expect consistency month to month."
The fall of RIM was even clearer when Nielsen's total share numbers -- all users, not just those who bought a smartphone in the last three months -- were compared.
In August, Android and Apple accounted for 43% and 28% of all U.S. smartphones in use, said Nielsen, a five- and one-point increase, respectively, over May. RIM meanwhile, fell three points in August to 18%.
The biggest factor in Android's rise in recent purchase share, said Gold, was the sheer number of new smartphones that have been released.
"I think we need to be careful how we take these numbers," said Gold. "They're not saying that there's decreased sales or interest in the iPhone. But they do show that Android is overwhelming the market with devices."
Naturally, people want the latest -- and theoretically greatest -- smartphone when they shop, argued Gold, and with the flood of new models powered by Android, it's no surprise that Google's operating system overpowers Apple's in the numbers game.
"That trend will only continue, which is why Android is taking so much market share," said Gold.
Don Kellogg, Nielsen's director of telecom research, agreed.
"Android is available from any U.S. carrier," said Kellogg, "and although Apple launched the iPhone on Verizon earlier this year, they haven't had a new model for some time."
Essentially, it's a battle waged between the many -- all the smartphone makers that produce Android devices and the carriers that support it -- and the few, represented by Apple and its two U.S. partners, AT&T and Verizon.
"It's Windows all over again," said Gold. "In Windows vs. Apple, why did Windows win? It was because Microsoft had a lot of people on their side."
Gold expects the same trend in smartphones. "I don't see how, longer term, unless Google messes up, Android loses the battle of creating more market share."
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His e-mail address is gkeizer@computerworld.com.
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