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Consumers are predisposed to spend more when their brains are in "down time" mode.

“Shop ‘til you drop” is so last-millennium. The proliferation of smartphones and tablets means that shoppers today are clicking “buy” even after they’ve dropped — into bed or the bathtub. 

This is terrific for retailers, since consumers are predisposed to spend more when their brains are in “down time” mode. But for those customers, their relaxation-induced splurges might lead to some buyer’s remorse. 

More than half of smartphone and tablet owners use their devices in bed, and about a quarter do in the bathroom, according to a Nielsen study conducted last year. It’s a safe bet that a number of them are shopping, according to a recent survey out of the U.K.

A division of online retailer Shop Direct Group asked 1,000 customers where they shopped: 43 percent said in bed, 18 percent said on the toilet and 14 percent said in the bath.

 Shoppers today do more research — checking comparison-shopping sites, reading user reviews and so on —  before making a purchase, said Heidi Cohen, president of Riverside Marketing Strategies. “What’s happened today with shopping is there’s a lot more time spent and there’s a lot more steps.”

 With only so many hours in the day and mobile devices that people carry practically everywhere, there’s some inevitable spillover of that pre-shopping into people’s private time.

“Convenience is also playing a part,” Sarah Quinn, marketing manager at On Device Research, said via email. “They have their mobile switched on and it’s usually with them all the time, so they don’t need to wait until the evening when they’re at home to switch on their PC.”

A study of American mobile shoppers conducted by On Device in conjunction with the Interactive Advertising Bureau found that nearly half of purchases take place at home.

But sinking into a bubble bath to do some online shopping might not be the best idea for someone trying to stick to a budget, and not only because they’ll be stuck replacing it if it falls in the water. Michel Pham, a professor at at Columbia University’s Business School, found that shopping while unwinding can be an expensive hobby. 

In Pham’s experiments, subjects in a state of relaxation thought items were worth more than they actually were and were willing to pay as much as 15 percent more for things than people in a neutral frame of mind.

“This effect seems to be caused by differences in relaxed and non-relaxed individuals’ mental construals of the value of the products,” he wrote. When relaxed, shoppers think about how enjoyable the purchase will be, rather than consider practicalities like price.

Sites are catching on and taking advantage of this, sending out emails or social media promotions at hours when customers are more likely to be unwinding — possibly with a glass of wine or a cocktail, which lowers inhibitions further. Andy Page, president of online flash sale retailer Gilt Groupe, told the New York Times last year that his site added 9 p.m. sales to take advantage of this buying behavior.

This type of shopping is likely to be more pleasant," Lars Perner, a marketing professor at the University of Southern California, said via email.  "People will tend to be less critical while in a good mood, meaning that people may be more likely to buy things that they would be more likely to resist during ordinary shopping trips."

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Santa was no match for tech-savvy shoppers during the holiday season. 

When it came to finding the best products and the best prices, more than half of consumers came armed with their cell phones to help them make purchasing decisions. And just as traditional brick-and-mortar retailers feared, many of those shoppers decided not to buy merchandise from stores they visited thanks to information they got via mobile phone comparison shopping. 

Those findings come from a study released Monday by the Pew Research Center’s Internet & American Life Project, which found: 

• 38 percent of cell owners used their phone to call a friend while they were in a store for advice about a purchase they were considering making.
• 24 percent of cell owners used their phone to look up reviews of a product online while they were in a store.
• 25 percent of adult cell owners used their phones to look up the price of a product online while they were in a store, to see if they could get a better price somewhere else. 

“Consumers are feeling like they have a leg up on retailers,” said Esther Swilley, assistant professor of marketing at Kansas State University, about the increasing use of mobile devices to bargain hunt. “They can get price quotes quickly, and they now realize, ‘I can do better than what you’ve got here.’ ” 

Not surprisingly, the under-50 crowd was more likely to use mobile devices for online product reviews, and urban and suburban cell phone owners were about twice as likely as rural users to have recently used their phones for product analysis. 

Minority mobile users were more apt to look up online reviews than white cell phone owners; and college-educated shoppers were more likely to dial for deals than those who did not attend college. 

Retailers who are worried about consumers’ new-found independence, she added, are going to have a hard time curbing these cell-phone price crusaders. 

Target recently moved to try and derail mobile deal seekers by asking some manufacturers to create Target-exclusive items that would make it harder to comparison shop. The retailer, along with many other merchants who rely heavily on in-store sales, don’t much like the growing habit of “showrooming,” an industry term for shoppers who use stores as a place to check out items and then buy products online at lower prices. 

Such fears, it turns out, are warranted, according to the Pew study. 

Researched asked respondents what actions they took after using their phones in stores to look up prices, and 37 percent said they decided not to buy the product at all. 

In addition: 

• 35 percent purchased the product at that store. 
• 19 percent purchased the product online. 
• 8 percent bought the product at another store. 

That’s just the beginning, said Eric Johnson, management professor and information technology expert at Tuck School of Business at Dartmouth University, who expects mobile devices will become a shopping mainstay. 

Retailers such as Target and Best Buy, he said, have been the most worried about how the technology will undermine sales because of the “petting-zoo phenomenon,” but they’ll have to learn to embrace it given the potential upside. 

Savvy merchants are using mobile technologies to “augment the shopping experience,” he explained, pointing to Wet Seal, the junior apparel chain, as a prime example. 

Wet Seal offers its customers an app that gives them suggestions for ensemble pieces, or accessories, when they scan codes on merchandise in the store. They can buy the products in the store, or go to a virtual shelf online and purchase the color or size they want if it’s not in stock, he said. Mobile users can upload the outfits to Facebook so friends can offer their “likes” or “dislikes” before shoppers buy. 

This type of mobile integration, he said, “is where the real excitement is.” 

Traditional retailers, he continued, “can’t just employ defensive moves to make it difficult to compare, but they have to find substantial ways to connect with the shopper in the shopping experience, and do that with mobile apps.”

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Target tries to fight off online retailers