Android dominates the smartphone market with 40.1% of U.S. smartphone owners using Android-based smartphones, according to a new report from comScore that measured mobile subscriber market share during the three month average period ending June 2011. Android adoption rose up 5.4 percentage points from the previous three month period.

Apple’s iPhone held the No. 2 position, with 26.6% of smartphone owners owning an iPhone, up 1.1% from the prior reporting period. RIM held the No. 3 position with 23.4% share, followed by Microsoft at 5.8% and Symbian at 2%.

According to the report, 78.5 million people in the U.S. owned smartphones during the three months ending in June 2011, up 8 percent from the preceding three month period.