ComScore has released its latest report on the U.S. smartphone market, and it suggests that Apple’s share of the U.S. OEM market is growing, while Android is continuing to dominate the U.S. operating system market. Samsung remains the top mobile OEM in the United States with a 24.8% marketshare, up 0.3 percentage points from the period prior. It’s followed by LG (20.9%, no change), Motorola (16.1 percent, down .9 percentage points), RIM (8.6 percent, down .2 percentage points), and Apple (7.5%, up .9 percentage points). Given the dominance by Samsung, LG, and Motorola, it comes as no surprise that Android now has a 33% grip on the U.S. smartphone operating system market — that’s up 7 percentage points from the last report. RIM’s BlackBerry OS dropped 4.6 percentage points to a 28.9% share of the market. It’s followed by Apple’s iOS (25.2%), Microsoft’s Windows Phone (7.7%), and Palm’s webOS (2.8%). The report also found that 68.7% of mobile users use their phone for text messaging. Hit the jump for the full release.