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Cell Phones Tracking Nightlife Activity 121

Roland Piquepaille writes "A Columbia University computer science professor has co-founded a New York-based company named Sense Networks to sell tracking software to other companies. It is also distributing a free version of this software, named Citysense, which shows on your cell phone where the wild things are happening in your own town. Citysense 'uses advanced machine learning techniques to number crunch vast amounts of data emanating from thousands of cell-phones, GPS-equipped cabs and other data devices to paint live pictures of where people are gathering.' Citysense is available today in San Francisco, before being soon deployed in Chicago and five other U.S. cities."
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Cell Phones Tracking Nightlife Activity

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  • by icegreentea ( 974342 ) on Sunday June 29, 2008 @03:46PM (#23992801)
    TFA is a bit unclear, but it appears that in order to use this system, you also have to feed it your own information. Seems like a fair trade off (as long as its opt-in, can opt-out blah blah, standard privacy issues).
  • Las Vegas (Score:2, Informative)

    by strabes ( 1075839 ) on Sunday June 29, 2008 @04:00PM (#23992903)
    Having been born and raised in Las Vegas, this type of service seems quite unnecessary in this town. After all, everyone knows where "the wild things are happening" here.
  • by vertinox ( 846076 ) on Sunday June 29, 2008 @04:05PM (#23992945)

    More seriously, it appears that this technology is GPS-only and not all folks have GPS-equipped phones. I don't understand GPS all that well and I'm wondering how this tracking software can locate them, do they have to consent to being tracked, etc.

    Actually, GPS isn't required to locate you with a cell phones. The technology exists to poll which cell phone towers your phone is polling and make a guesstimate of where you are based on that.

    With cell technology, you're not simply talking to one tower at a time because if you were traveling, then as soon as you were out of range of the tower, you would have the call drop. So the cell phones are actively polling the towers as you move to hand you off between the closest (or best signal in some case).

    This is how they locate you if you call 911.

    The downside is that if you are in a rural area, and have only 1 or even two towers (it takes three to triangulate), then they can't really tell where you are other than somewhere in a radius of the tower. So this technique only works within areas with high cell tower density.

    On a side note, you could always lend your cell phone to a girl when she goes to a Chip and Dale club and let the hilarity ensue when your friends show up there.

  • by imrtt ( 1287370 ) on Sunday June 29, 2008 @05:39PM (#23993599)
    I operate a free GPS tracking service ( []), so I know a thing or two about this topic.

    This is an interesting idea, but it won't catch on for a few more years. The problem is that only a tiny fraction of cell phones (I would estimate less than 1%) are capable of GPS tracking now. Of those people who have a compatible phone, most won't bother to install the app and remember to start it whenever they go out. Typical battery life when GPS is turned on is about 8 hours. So this is not an app that can run in the background 24/7.

    In the end, you will have something like 10 people in San Francisco who send data to their system. It is enough data to make sense of what's happening in the city? Not hardly.

    Give it another 5-10 years, and perhaps most phones will have GPSs in them. Perhaps battery life will improve enough to make continuous GPS tracking possible. Until then, this service, and other similar services, will have little value.

How many NASA managers does it take to screw in a lightbulb? "That's a known problem... don't worry about it."