ComScore put out its now monthly estimate of mobile market share today (based on a user survey of 30K respondents). As with IDC's numbers released earlier, Samsung is the top overall hardware maker in the US market. Among smartphone operating systems Android is number one and has been since roughly January 2011.
Below is the smartphone breakdown for March 2011:
Microsoft continues to struggle and does not seem to be gaining traction with Windows Phones (although some have pointed out that the rate of decline has slowed). Palm is entering the Nokia zone in terms of near disappearance from the US market. And the iPhone is flat according to these data.
Seemingly contradicting the data above, comScore earlier put out metrics that showed iOS in the US and Europe to have a reach that greatly exceeds Android. The iPad and iPod Touch make all the difference it would appear.
For comparison purposes here's the same comScore smartphone market share data for July 2010:
In the roughly nine months in-between RIM's share of the smartphone market has dropped about 12 percentage points.
Below is another view of mobile OS market share in the US from StatCounter: