• by Mark Walsh  @markfwal, May 3, 2012

More than three quarters (79%) of U.S. smartphone and tablet owners have used their devices for shopping-related activities, according to a first-quarter survey by Nielsen. The study showed smartphones are used more often than tablets for “on-the-go” activities.

The difference was most pronounced when it came to locating a store, with 73% using phones compared to 42% on tablets. Handsets were also preferred for using a shopping list, while shopping, (42% versus 16%) and redeeming a mobile coupon (36% to 11%). However, tablet owners are more likely to use their devices for making purchases, at 42% versus 29% of smartphone users.

The findings suggest the smartphone is the go-to research tool while out shopping, but the tablet is where the deal gets closed. If that’s the case, it likely has to do with the tablet lending itself more to making online purchases while relaxing at home and on a larger screen. And as tablets increasingly eat into time spent on desktop PCs and laptops, it makes sense that at least some e-commerce activity would shift to tablets as well.

While smartphones may be more popular when people are out and about, a majority of both phone (57%) and tablet users (66%) use their devices to research items before purchase. Mobile payments, however, haven’t really caught on with either group yet, with less than 30% of smartphone and tablet owners using their devices to pay for things at checkout.

A separate survey released Thursday by location-based marketing firm Placecast focused on comparing smatphones and feature phones in relation to m-commerce. It found that about 20% of all adult mobile phone users, equal to about 39 million Americans -- had used their handset to make an online purchase in the past year. That proportion rose to 34% among smartphone owners, somewhat higher than the 29% cited in the Nielsen research.

Placecast said overall interest in using phones for purchases has grown by eight percentage points in the past two years, with 38% of all mobile phone owners saying it’s at least somewhat important to be able to do so. That rate was again higher for smartphone users, at 59%.

The study also offered other stats on smartphone-wielding shoppers: 50% use a GPS/mapping app to find a retail location; 44% accessed the site of a retailer where they typically shop; 34% had downloaded a retailer’s app; and an equal number (24%) had either searched for a coupon to use at checkout or used a barcode-scanning app to comparison shop.

The Placecast research also indicated that people have become a bit more receptive to text-message marketing. About a third of mobile users (31%) who don’t already receive text ads said they are at least somewhat interested in such messages, provided they gave permission. That figure, equating to about 64 million consumers, is up from 28% in 2010.

Currently, only 4% of mobile users get text promotions. Within that group, however, nearly one in three said they are more likely to visit the store as a result, while a quarter are more likely to buy the product advertised. Smartphone users said texting generally is very important to them, compared to 35% of regular phone users.

The Placecast study results were based on a survey conducted by Harris Interactive in February among 2,262 adults from a nationally representative survey. It is the third in a series of studies called “The Alert Shopper,” conducted previously in the summer of 2009 and 2010.