Google's Android was the top smartphone operating system in the U.S. in the first quarter of 2011, overtaking the market share of Research in Motion's BlackBerry and keeping Apple's iPhone in the third position, according to ComScore.
Android runs 34.7% of the 72.5 million smartphones in the U.S. in the first quarter, the market research company said. Android-based smartphones accounted for 28.7% of the market at the end of the fourth quarter in 2010, when fewer smartphones -- 63.2 million -- were in use.
BlackBerry's share of the smartphone market dropped from a 31.6% share at the end of 2010 to 27.1% at the end of March, ComScore said.
Apple's iPhone share increased slightly from 25% to 25.5% over the first three months of 2011.
Meanwhile, the market share for Microsoft's new Windows Phone 7 and older Windows Mobile products dropped 0.9 percentage points, from 8.4% in December to 7.5% in March. Palm and the WebOS under Hewlett Packard dropped from 3.7% to 2.8% over the period.
The ComScore report is based on surveys of 30,000 U.S. mobile subscribers. ComScore reports have consistently shown that the U.S. market is different from the rest of the globe, where Nokia dominates .
ComScore said Android benefits from its support from several smartphone makers.
Samsung (which makes smartphones running Android and other platforms) was the top smartphone manufacturer, with 24.5% market share, followed by LG, with 20.9%, Motorola with 15.8%, RIM with 8.4% and Apple with 7.9%.
RIM's decline in the last half year has been fairly steep -- more than 10 percentage points -- since it held a 37.3% share of the U.S. smartphone market at the end of the third quarter in 2010.
RIM last week unveiled a new OS and two new smartphones among other new products and services at its BlackBerry World conference.
Microsoft CEO Steve Ballmer also attended the RIM event, and announced that Microsoft would invest in the BlackBerry platform with Bing search and maps.
The RIM announcements came just a week after the company warned that its first quarter earnings would be lower than expected and that smartphone launches would be delayed later into 2011. The warning resulted in some analysts downgrading RIM's stock rating and a slip in RIM's stock price.
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen , or subscribe to Matt's RSS feed . His e-mail address is [email protected] .
Read more about smartphones in Computerworld's Smartphones Topic Center.