iPhone Share Growing Faster Than Android Smartphones: Nielsen

Apple's iPhone is growing faster among new acquirers than Google Android smartphones. The open-source OS is the U.S. leader at 38 percent, Nielsen said.

Google's (NASDAQ:GOOG) Android creator Andy Rubin said Android is being activated on more than 500,000 smartphones and tablets each day, and yet there is mounting evidence that Android handset growth is flattening while Apple's (NASDAQ:AAPL) iPhone sales grow.

Nielsen is the latest research to pour gas on this contentious fire. The researcher discovered that while Android still paced the U.S. smartphone market with 38 percent market share through May (up from 36 percent in April), its growth of recent acquirers flattened over the last few months.

Android accounted for 27 percent of the new smartphone acquirers from March through May. While Android is still the leader in recent acquirers, that 27 percent figure matches its new acquirer growth from December through February, leading Nielsen to conclude that Android sales are being curtailed.

But from what? The iPhone 4 on Verizon Wireless (NYSE:VZW), which launched in January, could be the culprit.

Apple, whose U.S. smartphone share grew from 26 percent in April to 27 percent in May, saw its recent acquirer share grow 7 percent, from 10 percent from December to February to 17 percent from March to May.

The iPhone is on the upswing as Apple steams toward an iPhone 5 launch later this summer.

Nielsen's report follows data from from Needham's Charlie Wolf, who used IDC data to show that Apple's share of the U.S. smartphone market gained 12.3 percentage points to 29.5 percent in the March quarter while Android's share fell from 52.4 percent to 49.5 percent.

Nielsen also found that Microsoft (NASDAQ:MSFT) maintained its 1 percent market share for the fledgling Windows Phone 7 platform in May.

Research In Motion (NASDAQ:RIMM), which is operating under a black cloud of unprecedented negativity, saw its share drop from 23 percent to 21 percent and its recent acquirer growth dip to 6 percent from 11 percent from February.

Overall, Nielsen said 38 percent of mobile consumers now own smartphones, with 55 percent of those who purchased a new handset in the past three months buying a smartphone instead of a feature phone. That's up from 34 percent just a year ago.