Google's Android and Apple's iOS dominated the U.S. smartphone segment throughout 2011, ending the year with a combined 76.9 percent market share according to new data published by digital research firm comScore.

Smartphone ownership in the U.S. market reached 97.9 million in December 2011--smartphone owners now make up 40 percent of all mobile subscribers nationwide, comScore reports. Android devices make up 47.3 percent of the U.S. market, up 2.5 percentage points since September 2011. iOS was the only other mobile platform to exhibit growth during the period, increasing 2.2 percentage points over September to capture 29.6 percent.

Research In Motion's BlackBerry continues to stumble, slipping another 2.9 percentage points between September and December to make up 16.0 percent of the U.S. market. Microsoft's Windows platform fell from 5.6 percent in September to 4.7 percent in December, and Symbian faded from 1.8 percent to 1.4 percent.

ComScore reports that 74.3 percent of all U.S. mobile subscribers sent text messages in December, up from 71.1 percent in September. In addition, 47.6 percent of subscribers used downloaded apps (up from 42.5 percent), 31.4 percent played mobile games (up from 28.8 percent) and 35.3 percent accessed social networking sites or blogs (up from 31.5 percent).