FILE - In this Nov. 28, 2014 file photo, a Target shopper uses her iPhone to compare prices at Wal-Mart while shopping after midnight in South Portland, Maine. Increasingly, buying products online is like trading stocks: you can buy a copper mug or a coat and then hours _ or even minutes later _ it can go up and down in price. (AP Photo/Robert F. Bukaty, File)
A shopper uses a smartphone as she shops in a store. (AP)

Gamestop has no doubt that mobile devices have changed the way its customers shop. Smartphones and tablets now account for up to 68 percent of the traffic to the videogame chain’s Web site, where customers are frequently browsing products and looking up trade-in values for their old games.

One thing they’re not doing much of on mobile devices?  Buying stuff.

In fact, “purchasing through that phone probably wouldn’t even make the top ten list of engagement activities that they do,” said Jason Allen, the retailer’s vice president of multichannel.

Gamestop's experience reflects a trend seen throughout the industry: While there has been a surge in traffic to retailers' Web sites from smartphones, a proportionately big boom in sales on these gadgets have yet to appear. In other words, for all the time we spend swiping and tapping on our phones, we still aren’t especially willing to make purchases on them.

Instead, shoppers are largely using their phones as something of a personal, pocket-sized sales associate that helps them browse and research while they are in a store. That has prompted retailers to adapt their mobile strategies to help them do something counterintuitive: Boost in-store sales.

“We’re not overly focused on conversion on mobile, we really see it as a tool to drive traffic in our stores,” said Krista Berry, the chief digital officer of department store chain Kohl’s. Conversion is an industry term for when browsers become buyers.

At Kohl’s, executives say they have spent the last year and a half updating their app, in part to accommodate an in-store shopper who is more frequently searching for product reviews, watching video content about merchandise and sharing their finds on social media.  When customers are in Kohl’s stores and on the retailer’s Wifi network, customers spend more time on the app than when they’re not in the store, company officials said.

These behaviors have led Kohl’s to develop a new “in-store mode” for its app, in which users who walk into a Kohl’s store will be asked if they want to use a special version that is tailored for wandering the store. Kohl’s declined to say how the in-store mode will be different from its regular app experience, but said it would be available in September.

Big-box behemoth Target is also catering to shoppers who are using their phone to guide them through stores with a relaunched app that has a stronger emphasis on a tool that helps them building their weekly shopping list and an interactive map of each store in its fleet.

It’s easy to see why the company has moved in this direction: Since it installed free WiFi in its stores a few years ago, Target has found that the most-visited site, by far, is the retailer’s own Web site.

This enthusiastic embrace of in-store phone use might have seemed unthinkable in corners of the retail industry only a few years ago, when many brick-and-mortar chains were panicking about showrooming, the industry term for when shoppers would go to a store to check out merchandise, only to ultimately buy it online for a better price.  But that fear has largely dissipated as study after study has shown showrooming is not a huge threat.  In fact, several studies have found that the opposite behavior -- browsing online before buying in a physical store -- is more common.

Data from last holiday season provide additional evidence that we’re often in research mode when we’re on our phones: During last November and December, smartphones drove 31.2 percent of total traffic to e-commerce sites, but accounted for just 9.1 percent of online sales, according to IBM.

This climate has not only pushed retailers to change up their game plan, it has drawn technology startups into action.

StepsAway, for example, is a mobile Web site that aims to be a digital-era version of the famed Kmart Blue Light Special. StepsAway lists all the sales at a given mall, which shoppers can access when on the mall’s WiFi network. Retailers have the option of using it to offer special time-sensitive sales, such as a two-hour deal for 20 percent off on cashmere sweaters.

With all of these in-store mobile strategies, one of the biggest challenges is designing an on-screen experience that works for a wide variety of shopping trips.  At Whole Foods, app users who aren’t time-pressed can dig into the trove of product information that shows ingredients and details about where a product came from.

But they are also experimenting with ways to engage an in-store shopper in a hurry, including with a feature that allows users to order coffee, sandwiches or charcuterie as they set foot in the door.

“One of the things that I think this will do is not only speed up the process by which the customers can get in and out of the store, it allows them to not spend time in line,” said Jason Buechel, the chief information officer at Whole Foods.

Even as companies bend to the reality that shoppers, for now, are not buying many things on their phones, they haven’t given up on finding ways to make a small-screen sale.  Facebook, Twitter, Instagram, Google and Pinterest are all experimenting with their own version of a “buy button,” a one-click way for users to make a purchase without leaving their app or having to go through the cumbersome process of entering credit card numbers on other personal information.

But these nascent efforts have been met with some skepticism.

“Merchants that are intrigued by these offerings are wise to test and learn but to have low expectations,” Sucharita Mulpuru, an e-commerce analyst with Forrester Research, wrote in a recent blog post.

That’s because, Mulpuru says, there are plenty of potential challenges to adoption. On Twitter and Instagram, for example, users see the most recent posts in their feed, meaning if they aren't logged in at just the right moment, they have little chance of seeing the "buy" button. Pinterest, on the other hand, is full of images of old merchandise that is no longer available for sale, which could be confusing for users who are ready to spend.