When you go to a shopping mall — if you ever do — there’s a good chance you’ve got a smartphone turned on in your pocket or bag. And if you do, you may be providing valuable data to that property’s owners, who can follow you around like a hawk to figure out how much time and money you’re there to spend.

As the Wall Street Journal reports, malls are adding one more tool to the box they’re using in a bid to stay relevant and solvent: customer tracking data.

We’ve been covering the slow, painful demise of the American mall — and many of the retailers in it — for a few years now, and it’s not slowing down. Just in the first three months of this year, for example, we’ve had stories about malls going into foreclosure; malls leasing empty space and trying to draw supermarkets; and investors snapping up dying malls or betting current owners will default.

So given all those danger signs, it’s no wonder malls would be trying literally everything they can think of to bring shoppers back and convince them to spend more money.

A lot of thought goes into mall design: Placing stores, displays, places to sit, places to eat, and other amenities in the “right” order can increase or decrease hjow long people stay around, for example. But landlords find it easier to design with data on hand, and that’s where your phone comes in.

When you connect to a mall’s WiFi — as customers often do, because the LTE data signal strength inside many malls is atrocious — you have to agree to some kind of terms and conditions page. Basically nobody ever reads those, but some can include you agreeing to have your data used, or will send you personalized discounts and offers as you move through the mall, in exchange for acess to your data.

The patterns are all over the place, one mall owner told the WSJ. Some shoppers may only come twice a year but spend five-figure sums each time; other patrons may come weekly but barely buy anything. “There is no one silver bullet to reach all of them,” he told the Journal.

The tracking is basically the physical version of the kind of online tracking we’ve had to accept as an (occasionally invasive) reality of modern life: Mall landlords use the data to see how long shoppers stay in the mall, how long they hang out in or near particular stored and displays, and where you came from before and head to after shopping with them. They can also match location data with your social media or email accounts to target ads to you.

The stores themselves have been deploying shopper-tracking technologies for years. Back in 2013, Nordstrom got called out for using in-store WiFi to track customers; after the public got ticked off, they stopped the practice.

Apple blocked retailers’ ability to use your iPhone’s MAC address to track you in a 2014 iOS release by randomizing those MAC addresses and making them not persistent.

Target, meanwhile, started testing in-store beacons linking to customers’ smartphones in 2015, and Rite-Aid started deploying the same kind of technology in 2016.

In the meantime, if you want to keep your mall activities to yourself… consider airplane mode.

Shopping Malls Are Tracking Your Every Move [Wall Street Journal]

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