Your Cell Phone Is Watching You

Tracking devices were once a staple of old science fiction and action movies. One typical scene: The good guy slaps a tracer on the villain's getaway car and follows him -- at a safe distance -- to his lair for the final showdown. Or a team of leering, white-coated technicians forces a microchip-sized homing device into the hero's brain cavity.

These days, such scenarios aren't so fantastical. For blanketing the United States are 140 million human-tracking devices: cellular phones.

When you place a cellular phone call, your phone seeks out the nearest receiving tower, which serves a discrete area or "cell." The tower routes the call to its destination. If you leave the cell area before your call ends, the call is bumped over to the corresponding cell tower, thereby tracking your rough location.

"Rough" is the operative word: While urban centers, which contain many cell towers, can relay your location with some accuracy, those odds go down in rural areas, where towers are fewer and cell service is often spotty.

But in the coming months, the tracking ability of cell phones will grow exponentially -- not just in its power to monitor users, but also in the way it can be used for commercial gain.

Last year, the Federal Communications Commission ordered cellular companies to equip all new cell phones with Global Positioning Satellite tracking devices that can pinpoint a user's location to within 300 feet, anywhere on the planet. The agency ordered the move at the behest of law enforcement agencies, who have long wished to be able to tell where 911 calls made on cell phones originate.

To a degree, cellular companies have reacted to the FCC's order with distaste. The GPS chips will add about $20 to the cost of each phone, which are often given away free with cellular service plans.

But the companies are also rubbing their hands with glee at the potential profits. As regular Internet users know, marketers believe there's money to be made from information about people's daily activities and habits. Log on to a typical website, and it may plant a "cookie" -- a piece of code that identifies users -- on your hard drive. With that information, websites can track your surfing habits and tailor the content of advertisements accordingly.

Cell phone companies are aware of the potential backlash from consumers; a Verizon Wireless spokesperson told the technology news website CNET.com that it currently has no plans to release information about customers' day-to-day whereabouts to commercial third parties. Still, none of the cell companies are saying they won't try to use the information for their own purposes.

One way cell companies could profit is by selling advertising that would be displayed on cell phone screens. In the near future, your cell phone could turn into a miniature billboard, alerting you, for example, to nearby restaurants at lunchtime or to sales at the local mall.

This won't happen overnight. Cellular companies have lobbied for and received a temporary stay from the FCC's order to install the GPS chips, although that reprieve is set to expire later this year. The FCC ruling also allows companies to ease into compliance, giving them until 2005 to make all cell phones GPS-equipped.

But in the meantime, you're not safe from cell-phone marketing: Some companies, such as marketers PangoNetworks, are already making use of today's more limited location tracking technology.

Pango sets up zones called "hot spots" within businesses or shopping malls. Hidden sensors can detect your phone or Palm Pilot, upon which the system hums into life, sending ads for merchandise you might be standing near and compiling data about your shopping habits: What stores have you visited? Did you linger near the wrinkle-free khakis or by the animatronic Hello Kitty display? Boxers or briefs?