There’s a bigger market for “you are here” than you thought.

Here’s the first thing to understand about most location apps: Once you give them permission to track your location, they’ve got it until you turn it off. That means when you clicked “Accept” that one time, most apps have the authority (and ability) to collect information about you while you go about other activities. In fact, that one app may have shared location data with other apps … again, all with your “permission.”

So. What happens next?

If you’re like most people (me included, until recently) the answer was I don’t know.

Last week, the New York Times answered that question. They certainly weren’t the first, but they absolutely have the largest reach, and their journalists know how to tell a good story. You can read the full article for yourself, but let me quote directly the crux of their findings:

At least 75 companies receive anonymous, precise location data from apps whose users enable location services to get local news and weather or other information, The Times found. Several of those businesses claim to track up to 200 million mobile devices in the United States — about half those in use last year. The database reviewed by The Times — a sample of information gathered in 2017 and held by one company — reveals people’s travels in startling detail, accurate to within a few yards and in some cases updated more than 14,000 times a day. These companies sell, use or analyze the data to cater to advertisers, retail outlets and even hedge funds seeking insights into consumer behavior. It’s a hot market, with sales of location-targeted advertising reaching an estimated $21 billion this year. IBM has gotten into the industry, with its purchase of the Weather Channel’s apps. The social network Foursquare remade itself as a location marketing company. Prominent investors in location start-ups include Goldman Sachs and Peter Thiel, the PayPal co-founder.

Unlike sometimes-justified / sometimes-not criticism of the New York Times, I don’t see a “big business conspiracy” around every corner. Most business people are people too — they’re your colleagues, siblings, parents, and friends. They’re also customers and users of these products. Most businesses simply are trying to earn an honest profit providing a reasonable service in an increasingly competitive world.

But the fact remains: now that these apps have your permission (and there are a lot of apps that do this), and they have the location data your phone generates, they create something of value. That value creation is like crack cocaine to the average marketing VP, chief executive, or controller. In many ways, location data is some of the best data to have because it is not based on your opinion (likes, shares, comments) but rather it’s based on your behavior. As our grandparents taught us: Actions speak louder than words.

And wow are we ever speaking with our actions. You may wonder if you are “interesting enough” to warrant deeper interest from Google (I did). But when you consider the vast array of potential interested parties, you can see how you just became the most interesting person in the world. Let’s look at just a few of the reasons other parties are interested in your location data:

· Retailers (and investors in retail operations) are interested in actual foot traffic, not “estimates” of foot traffic. By merging mobile phone data with real-time foot traffic, retailers know the quality of potential customers as well as the quantity of them.

· Employers love location data. It helps them reconfigure building layouts to optimize placement of both individuals and teams. On the darker side, it also allows employers to know how often you use the restroom, if you and a colleague are having, ahem, a relationship, or how long you spend tethered to your desk.

· The days of ambulance chasing lawyers are long gone. With location data, they can send ads to any mobile phone in the emergency room of your local hospital.

· Law enforcement is a special case. They can subpoena your mobile phone records for a variety of legal reasons, but usually with probable cause. But with the technology available to advertisers and others, law enforcement can watch known high-crime areas and merge that data with publicly-available mobile phone data — data that you freely provide.

That’s just a few. I could go on.

I’ll bet even with those few examples, you are getting a sense for the broader market for “you are here” than you ever thought possible. Yes, you’re getting a “free” service, but you’re also trading away more than you bargained for.

Even at this point, I can see an argument that goes like this: Well, this is aggregated data, right? If it’s aggregated with millions of other people (or at least dozens of others), picking me out of a crowd is difficult. I can still blend in, right?