Beware: Some smartphone apps collect location data to sell to advertisers, retailers, and more

“The millions of dots on the map trace highways, side streets and bike trails — each one following the path of an anonymous cellphone user,” Jennifer Valentino-Devries, Natasha Singer, Michael H. Keller and Aaron Krolik report for The New York Times. “One path tracks someone from a home outside Newark to a nearby Planned Parenthood, remaining there for more than an hour. Another represents a person who travels with the mayor of New York during the day and returns to Long Island at night.”

“Yet another leaves a house in upstate New York at 7 a.m. and travels to a middle school 14 miles away, staying until late afternoon each school day. Only one person makes that trip: Lisa Magrin, a 46-year-old math teacher. Her smartphone goes with her,” Valentino-Devries, Singer, Keller and Krolik report. “An app on the device gathered her location information, which was then sold without her knowledge. It recorded her whereabouts as often as every two seconds, according to a database of more than a million phones in the New York area that was reviewed by The New York Times. While Ms. Magrin’s identity was not disclosed in those records, The Times was able to easily connect her to that dot.”

“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. These companies sell, use or analyze the data to cater to advertisers, retail outlets and even hedge funds seeking insights into consumer behavior,” Valentino-Devries, Singer, Keller and Krolik report. “Businesses say their interest is in the patterns, not the identities, that the data reveals about consumers. They note that the information apps collect is tied not to someone’s name or phone number but to a unique ID. But those with access to the raw data — including employees or clients — could still identify a person without consent. They could follow someone they knew, by pinpointing a phone that regularly spent time at that person’s home address. Or, working in reverse, they could attach a name to an anonymous dot, by seeing where the device spent nights and using public records to figure out who lived there.”

Read more in the full article here.

MacDailyNews Take: It’s not so anonymous when the data basically screams your home address.

How to turn Location Services on or off: Settings > Privacy > Location Services.

How to turn Location Services on or off for specific apps:

1. Go to Settings > Privacy > Location Services.
2. Make sure that Location Services is on.
3. Scroll down to find the app.
4. Tap the app and select an option:
   – Never: Prevents access to Location Services information.
   – While Using the App: Allows access to Location Services only when the app or one of its features is visible on screen. If an app is set to While Using the App, you might see your status bar turn blue with a message that an app is actively using your location.
   – Always: Allows access to your location even when the app is in the background.

[Thanks to MacDailyNews Readers “Fred Mertz,” “Dan K.,” Lynn Weiler,” and “TJ” for the heads up.]


  1. Why not name the apps? Oh, but it’s any app! No not really. The story lists a couple apps but makes it sound like any app you use it selling your data. They need to get the list of apps that are selling your data, that would be the story

  2. You’d have to be a fool to use ANYTHING connected to the web at this point without taking precautions. All of them do it to an extent. This should just be conventional wisdom. There is no such thing as a safe space online.

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