A survey of 3,600 US mobile consumers by Author Commerce found that 15% of mobile users have made purchases on their phones.This number is broadly consistent with other studies and surveys (see links below) for the US market.
In this survey population slightly less than 50% of respondents reportedly owned smartphones, whereas the number is 23% to 25% in the overall US mobile population. So the results can't be directly extrapolated to the population of mobile users.
More findings (nearly verbatim):
A striking datapoint above is that 60% want store inventory information; while "only" 25% want offers or coupons while shopping. An equal percentage said they performed in-store price comparisons. As barcode scanning becomes more commonplace and easier to use, this latter figure will go way up.
Separately, Insight Express recently found that 82% of survey respondents used their mobile phones while shopping in stores.
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