Samsung continued to dominate the U.S. cell phone market, while leading smartphone platform RIM lost some market share to the Android OS in the third quarter, according to Wednesday data from comScore.

By sheer volume, Samsung remained the leading handset manufacturer with 23.5 percent of the market, up 0.7 points from the previous quarter. LG, Motorola, RIM, and Nokia followed next with 21.1 percent, 18.4 percent, 9.3 percent and 7.4 percent of the market respectively. Smartphones penetrated 25 percent of the U.S. cell phone market, up from 15 percent from the last quarter.

On the OS front, RIM's BlackBerry OS lead with 37.3 percent of the market, but this share was down 2.8 points from the previous three months. Apple's iOS came in second with 24.3 percent, followed by Google's Android platform with 14.9 percent of the market, a 6.5 percent increase. Microsoft saw its market share slide to 10 percent, down 2.8 percent from the last quarter; its updated Windows Phone 7 OS hits the U.S. on Nov. 8.

ComScore also looked at the most popular uses of mobile phones apart from talking. Sixty-six percent use their phones to text, while the fastest-growing category here was downloading apps. A third of those surveyed used downloadeded apps, up 2.5 percent from the previous quarter.

Separate Monday reports from NPD Group and Canalys found that the Android OS captured about 44 percent of the U.S. smartphone market this quarter, ahead of Apple and RIM.