13.1 million consumers access retail content via mobile phone; 8.2 million visit mobile commerce web sites, 4.2 million engage in text messaging and 3.2 million have downloaded and used mobile apps, according to the comScore/Millennial Media Mobile Retail Study. The numbers add up to more than 13.1 million because many mobile shoppers engage in more than one method.

The study finds that mobile shoppers skew young. 36% are age 25-34, 22% are 18-24 and 5% are 13-17, say web and mobile web measurement firm comScore Inc. and mobile advertising technology and research firm Millennial Media. 21% of mobile shoppers are age 35-44, 11% are 45-54, 4% are 55-64, and 2% are 65 and older. The numbers add up to more than 100% due to rounding.

Mobile shoppers tend to be more affluent than mobile web users overall, the study says. 34% of mobile shoppers and 27% of mobile web users make $100,000 or more a year. 18% of mobile shoppers and 15% of mobile web users make $75,000-$100,000. 21% of mobile shoppers and 20% of mobile web users make $50,000-$75,000. 16% of mobile shoppers and 23% of mobile web users make $25,000-$50,000. And 11% of mobile shoppers and 16% of mobile web users make less than $25,000. The numbers for mobile web users overall do not add up to 100% due to rounding.

The study also found that mobile shoppers use their phones for a variety of shopping activities. 52% of mobile shoppers use their phones to help determine if a product is needed, 42% to perform research to help decide which products fulfill a need, 38% to make a purchase, 29% to comparison shop for a specific product, and 12% to evaluate a product after purchase, the study says.

“Mobile retail users are affluent, tech-savvy consumers that rely on their mobile devices to guide them through every step of the purchase process,” comScore and Millennial Media conclude. “It has become imperative for retail brands to commit to a mobile strategy to connect with these consumers where they are currently researching, comparing and purchasing products.”

The study is based on three surveys of mobile consumers on various comScore panels: one panel consisting of 39,000 mobile phone users, one of 15,000 and another of 6,576.