Google's wildly popular mobile Android operating system claimed 46.9% of the smartphone market from September-November 2011 - up 3.1 percentage points from the prior three-month period.
According to ComScore, Apple maintained its #2 position, steadily increasing by 1.4 percentage point to 28.7 percent of the smartphone market.
RIM ranked third with 16.6 percent share, followed by Microsoft (5.2 percent) and Symbian (1.5 percent).
Meanwhile, device manufacturer Samsung weighed in as the top OEM with 25.6 percent of US mobile subscribers (up 0.3 percentage points), followed by LG with 20.5 percent share and Motorola with 13.7 percent share.
Apple strengthened its position at #4 with 11.2 percent share of total mobile subscribers (up 1.4 percentage points), while RIM rounded out the top five with 6.5 percent share.
As expected, the rate of text messaging continued to increase from September-November, rising 2.1 percentage points - as 72.6 percent of US mobile subscribers now use the service on their mobile devices.
Downloaded applications were run by 44.9 percent of subscribers (up 3.3 percentage points), while browsers were used by 44.4 percent (up 2.3 percentage points).
Accessing of social networking sites or blogs jumped 2.1 percentage points to 33 percent of mobile subscribers. Games were played by 29.7 percent of the mobile audience (up 1.2 percentage points), while 21.7 percent listened to music on their phones (up 1.0 percentage points).