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Have a Wi-Fi-Enabled Phone? Stores Are Tracking You

jfruh writes "Call it Google Analytics for physical storefronts: if you've got a phone with wi-fi, stores can detect your MAC address and track your comings and goings, determining which aisles you go to and whether you're a repeat customer. The creator of one of the most popular tracking software packages says that the addresses are hashed and not personally identifiable, but it might make you think twice about leaving your phone on when you head to the mall."

26 of 323 comments (clear)

  1. first by Anonymous Coward · · Score: 5, Informative

    To turn off the wifi

  2. Turn off wifi by Anonymous Coward · · Score: 5, Insightful

    Most smart phones allow you to turn off wifi.
    I keep mine off most of the time unless I need it that also includes GPS and Bluetolth

    1. Re:Turn off wifi by Spiridios · · Score: 5, Informative

      Of course marketing guys are going to be more creative in tracking you. I automatically turn off my WiFi when I hit the road. I use a car dock with my Droid, and I use a simple app that detects when I put it in the car dock. It will turn off WiFi, and turn on Bluetooth. When I remove it from the car dock, I could either restore the previous WiFi setting, or leave it off. I generally leave it off unless I'm going somewhere I trust the WiFi, like home or the office.

      Android has a nifty little program called Llama that I use for pretty much the same thing. Get home, WiFi on, leave the house, WiFi off. The tool has other benefits too, like going into silent mode when home at night so random emails don't wake me. But thanks to Llama, I usually don't have to mess with my WiFi settings unless I'm in a strange place that I know has free WiFi and I want to leech off of it instead of my data connection.

    2. Re:Turn off wifi by JustOK · · Score: 4, Funny

      From signature:

      I'm not that concerned with Karma, I post when I think I have something to add

      How does the equivalent of "mod parent up" add to the discussion? The parent is at +5, but I doubt people just blindly follow what some random person says it should be modded to.

      So true. mod this up!

      --
      rewriting history since 2109
    3. Re:Turn off wifi by javaguy · · Score: 3, Informative

      The permissions for the Llama app include:
        - Read calendar events plus confidential information
        - Add or modify calendar events and send email to guests without owners' knowledge
        - Read your contacts
        - Pair with Bluetooth devices

      That seems to be excessive given the functionality of the app.

    4. Re:Turn off wifi by Abstrackt · · Score: 3, Funny

      So true. mod this up!

      Okay.

      --
      They say a little knowledge is a dangerous thing, but it's not one half so bad as a lot of ignorance. - Terry Pratchett
    5. Re:Turn off wifi by Spiridios · · Score: 3, Interesting

      I've been using Llama pretty much since I got my first Android phone almost two years ago and they've been pretty open about why they need such and such new permission. In fact, if you read through the description, instead of jumping to the permissions directly, you'll see a description of why they need a few of the permissions, including calendar access. Put simply, if you want a 3rd party program to do things, you kind of need to grant permission to do those things. Granted, it would be nice if Android allowed you to grant subset permissions only for the things you use, but this is unfortunately how Android is.

  3. Change your MAC address by Anonymous Coward · · Score: 5, Interesting

    Change your MAC address to a pseudo-random one every time you go out of your main home or work environment. It's possible on android and iOS devices.

    1. Re:Change your MAC address by Jane+Q.+Public · · Score: 3, Insightful

      "Change your MAC address to a pseudo-random one every time you go out of your main home or work environment. It's possible on android and iOS devices."

      This would be of absolutely no help with an in-store tracking system. They don't care what your MAC address IS, they just use it to track you in the store.

      And despite what the software vendors claim: a tracking system that assigns a MAC address to you walking down an aisle *IS* personally identifiable... as long as you are in the store.

  4. Don't Just Turn Off Wifi by FSWKU · · Score: 4, Insightful

    Avoid places where this kind of garbage is known to be in use. Turning off the wifi means you have to sacrifice some of the functionality of your phone just to not be tracked. Similarly, the op-out is crap as well. Why should I have to opt out? And what's wrong with the door sensors that have been in use for years to figure out conversion ratios?

    Not that I've gone into a mall recently, but seeing any of the stores using this system would be the best way to make sure I never come back.

    --
    "So after all this, you make my case for me. To end this stalemate, you must die..."
    1. Re:Don't Just Turn Off Wifi by LordSnooty · · Score: 4, Insightful

      You're wandering around shouting "i am this address, do you have service" so you can't be surprised if some recipients note that down.

  5. Gas points by badford · · Score: 3, Insightful

    They will track your movements with facial recognition cameras.

    Insurance company will know how much butter, beer and beef you are buying.

    Your car will track your driving habits and your TV will track your entertainment.

    They will know when you are happy, sad, indifferent or lonely and will provide a product or service that will hit the spot.

    Just relax. They have your best interest firmly in mind

    --
    -badford
  6. Re:Why does this matter? by Anonymous Coward · · Score: 4, Insightful

    No, that's not what it means at all. It means they'll be able to better tailor their store to profit off of you. Generally, that's not a good thing for you.

  7. Here's what's really scary... by neiras · · Score: 5, Insightful

    Any smartphone can see all the MAC addresses of all phones and access points around it, bluetooth or WiFi (if enabled of course). With GPS positioning on most of those devices and a Giant Corporate Big Brother aggregating the results, all of us are reporting on our proximity to each other.

    We all know that Google's wifi geolocation stuff works this way - by tracking which fixed wifi base stations are in range and correlating with a GPS fix. People forget that Google can also identify other phones within range of your phone, and they know which Google accounts are attached to those devices.

    Google really does know who is sitting next to you on the train or in the coffee shop, who your jogging partner is, and which whore you visit when your wife leaves your general vicinity.

    I bet they do some amazing automated profiling. This guy is a garbage man and works with these people, that guy likes to sit in coffee shops and this woman is usually also present, she's not his wife, so lets advertise couples vacations and cheater sites, this other woman visits a preschool every day and is probably a parent, let's suggest other parents from the same preschool as her Google+ friend...

    1. Re:Here's what's really scary... by Jah-Wren+Ryel · · Score: 3, Informative

      We all know that Google's wifi geolocation stuff works this way - by tracking which fixed wifi base stations are in range and correlating with a GPS fix. People forget that Google can also identify other phones within range of your phone, and they know which Google accounts are attached to those devices.

      While that is certainly a possibility, I doubt that it is currently happening because it requires putting the wifi nic into monitor mode in order to sniff for wifi packets from nodes that are not associated with the same access point or ad-hoc network. The vast majority of wifi nics can not transmit when in monitor mode - thus making it useless for normal networking, which would tend to tip people off pretty quickly that something wasn't kosher.

      If you have documented evidence of google using monitor mode on people's phones, bring it on. That is the kind of thing that needs to be widely publicized if it is happening.

      --
      When information is power, privacy is freedom.
  8. Re:Why would it matter if it were hashed? by amorsen · · Score: 3, Insightful

    Isn't a hashed MAC address going to be the same every time? Seems like it would be easy to match the phone to a person if they made a couple credit card purchases on separate trips into a store.

    Correct, hashing does not do anything useful here except keep up the pretence. Well it prevents multiple-vendor networks from combining logs from different vendors, but I bet all monitoring devices from a single vendor use the same hash.

    --
    Finally! A year of moderation! Ready for 2019?
  9. Re:Why does this matter? by Jah-Wren+Ryel · · Score: 4, Interesting

    No, that's not what it means at all. It means they'll be able to better tailor their store to profit off of you. Generally, that's not a good thing for you.

    That is worth repeating. All of this "personalization" stuff is not about making your shopping experience better, it is about maximizing the amount of money you spend. Any benefit to you is purely incidental.

    --
    When information is power, privacy is freedom.
  10. I Smell a DOS prank by Jah-Wren+Ryel · · Score: 5, Interesting

    Presumably they are looking for the initial broadcast packet that starts the handshake to establish a wifi connection with a base station. Seems like you could mess with these guys if your phone had an app to dynamically change the MAC address on every handshake, you could also speed up the rate of such handshake initiations. Wander the aisles for a half hour and the store's now got a million bogus entries in their tracking database.

    --
    When information is power, privacy is freedom.
  11. Re:Why does this matter? by calzones · · Score: 5, Interesting

    The trouble starts when all mac address's activity gets logged into big data and stays there.
    Then later on, your mac address gets cross-referenced with your real name and phone number and personally identifying data some day (because, for example, you may frequent Starbucks or locations that feature free wifi).

    Suddenly, without anyone really trying, your every movement throughout the day just became trackable and they know how to reach you.

    --
    Asking people to think is like asking them to buy you a new car
  12. Re:Here's what's really scary... not really... by _avs_007 · · Score: 4, Interesting

    Not that it matters, but it doesn't work that way... (My full time job involved researching proximity algorithms)... Using Wifi as proximity, you can tell that say these 5 particular people are in a room, but you have zero idea the spatial relation of each of these 5 people to each other, without the aid of other sensors. Wifi or bluetooth will not give you spatial relationships in any meaningful manner.

    For example, if my signal strength to the AP is 80%, and your's is 80%, that does not mean we are next to each other. We can be on opposite sides of the AP, or we can be at some other arbitrary location, where each of us has a different obstacle blocking the direct line of site to the AP, reducing the signal strength by differing amounts. Plus we have no idea what the transmit power is on each device.

    You may be able to get a reasonable guesstimate of proximity to the AP, but not spatial orientation to the AP. (ie, you are within 20 ft of the AP, but you don't know in which direction), and certainly not between each peer. The phone will not be able to give you proximity information to another phone using wifi, because the stock chipset on Android and iOS does not give you access to read these beacon packets from arbitrary un-connected devices. I've been able to get it to work in the lab, but only when I use specific hardware/chipsets, with special drivers/firmware.

    So all I'm saying is that people are making this to be a bigger deal than it is.

  13. Don't use 4G constantly by davidwr · · Score: 3, Informative

    Turn off "location" and other "always want the network" apps that you don't need. Put your mail in "on demand" rather than "periodically polling" mode. Set your phone so the only thing it's routinely monitoring for over the air are incoming phone calls and texts.

    At this point your WiFi will be a waste of battery when you aren't actually using your phone.

    Now you can turn off your WiFi and save your battery.

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
    1. Re:Don't use 4G constantly by Jafafa+Hots · · Score: 4, Funny

      Me, I leave my cell phone at home.
      First, I never have a problem with the battery running out during a call...
      Plus I never have calls come in at inconvenient times.
      Also, I don't have to remember to shut it off in movie theaters and doctor's offices.

      These advantages are so great, I'm thinking of inventing a cell phone that can't be taken from your home. Maybe use some kind of tether.

      --
      This space available.
  14. just don't automatically join public wifi by pikine · · Score: 5, Informative

    Actually, you don't even need to turn off wifi. Just set your phone to not automatically join any public wifi. Wireless clients, including the phone, compiles a list of access points you can join using the ESSID broadcast from the access point. In other words, the access points just dumbly advertise their presence and don't know who are looking until your device tries to join.

    --
    I once had a signature.
    1. Re:just don't automatically join public wifi by shutdown+-p+now · · Score: 4, Informative

      Because it's not FUD, and you're wrong.

    2. Re:just don't automatically join public wifi by fearofcarpet · · Score: 3, Interesting

      Still it seems like collecting data for no obvious reason, just to know that some one came into the store who spent time in the Shoes department 6 weeks ago.

      I think the idea is that information now has value, particularly when it can be associated with consumer habits. Whether or not the grocery store cares how frequently a particular MAC address visits their store, when compiled into a large enough data set--so the logic goes--and cross-referenced with other large data sets, you can mine information that would be otherwise impossible without something intrusive like a survey. The MAC address also contains information about the chipset in your phone, when it was manufactured, etc. It isn't that much further to guessing your income, where you live, and eventually your shopping habits. Even without knowing your name, you could imagine a "smart" grocery store adjusting prices in real-time just, sort of like how airlines drop cookies to see if you have already searched for a ticket so they can keep the price high just for you. It's the high-tech version of the Ralph's Club Card; they want you to use it when you make purchases to track you, but now they can do it without your name or any personal information or anything proactive on your part.

      My feeling is that people find it creepy when a computer knows their name. Not many people wants to walk into the grocery store and hear a computer say "Hey Bob Smith, nice to see you again! Pizza bagels are on sale, and I know how much you like those." But if the grocery store sees "consumer type A431" approaching, the sign for pizza bagels may light up and blink "Sale! Sale! Sale!" which is intrinsically less creepy despite accomplishing the same thing. I could imagine doing that just with you MAC address and your approximate height and weight, which is easy to get from the self-checkout machine (it has a camera and weights things). The computer says "5'9", 235 lbs, $500 phone; clearly a Slashdot reader. I'll put the Hot Pockets, Mountain Dew, and hand lotion on special next time I see that MAC address hash."

      --
      Actually, I wrote my thesis on life experience.
  15. Your phone still scans by dutchwhizzman · · Score: 3, Interesting

    Your phone will still occasionally be sending packets to see if a known access point/SSID will reply. This is so access points with "hidden" SSIDs will still be found. Most devices just do this and there is no option to disable it, apart from disabling wifi completely. This is enough to see if someone with wifi enabled on their device is hanging around.

    Even more disturbing, if an access point with the correct SSID replies with no encryption, a lot of devices will automatically try to attach to that AP. By mimicking the identification protocol the device asks to use, you can even get it to attach to your rogue access point; just tell it it's credentials are accepted and it will merrily use your AP without any user interaction.

    --
    I was promised a flying car. Where is my flying car?