Android reigns as the top smartphone OS in the U.S. with a 39 percent slice of the market, according to a report out today from Nielsen.
In second place is Apple's iOS with a 28 percent share, followed by RIM's Blackberry with 20 percent.
Trailing the three top platforms, Microsoft's Windows Mobile and Windows Phone 7 combined grabbed 9 percent of the market, leaving HP's Palm/WebOS with 2 percent, and Nokia's Symbian also with 2 percent, Nielsen said.
Looking at the mobile industry by device makers, Apple is the only company making smartphones with iOS, giving it the leading share among U.S. consumers at 28 percent. That leaves some of the other device makers more fragmented with smaller chunks of the market.
Other top device makers include HTC with 14 percent of Android customers and 6 percent of users running Windows Mobile/Windows Phone 7. Motorola holds 11 percent of the Android market, while Samsung claims 8 percent of Android customers and 2 percent of those using Microsoft's mobile OS.
These latest results show a big boost for Android, a slight gain for Apple, and a downturn for RIM, compared with Nielsen's March numbers when the three top players were more evenly matched. Just a few months ago, Android owned 29 percent of the market, Apple's iOS had 27 percent, and RIM's BlackBerry OS also 27 percent.
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At the same time that Android continues to surge and Apple prepares to launch its next iPhone, RIM seems to be stuck in neutral. Hit by weaker handset sales amidst a more competitive market, the BlackBerry maker this week announced plans to lay off 2,000 employees. RIM has been criticized for its top-heavy management structure, which some analysts believe has led to a failure to innovate.