
AdMob's latest monthly metrics report shows that Android-based handsets are growing as a percentage of overall requests. This month's report also shows the rise and fall of various handsets over a period of nearly three years. AdMob also takes pains to counter criticism it has received by being very explicit about what its data do and do not reflect:
The report is based on the ad requests we receive from our network of more than 15,000 mobile Web sites and iPhone and Android applications. The data contained in the report is a measure of mobile data usage and does not represent the traditional view of market share based on the number of handsets sold.
And now for the data:
The following tables reflect handsets responsible for mobile Web and app views on the AdMob network (US and UK). Note the shifts from 2007 to 2009: The rise of Apple, HTC, RIM and Samsung in the UK; and the fall of Motorola (and to some degree RIM) in the US.


The following compares US smartphone OS share on AdMob's network in Decemberr 2008 vs. September 2009 (bottom):

None of these are market share numbers per se, as AdMob is now careful to point out. But they do reflect directional trends in the broader market.