"Wherever you carry your phone, the government can go to your wireless provider and use those records to figure out where you are," says the Electronic Frontier Foundation's Jennifer Granick.
Of course, this information could save your life; cell phone tracking has assisted in locating kidnap victims and people stranded in the wilderness. But law enforcement has also used the technology to track people without probable cause. Documents obtained via a Freedom of Information Act lawsuit by the ACLU, the EFF, and the Center for Democracy and Technology reveal that the state of New Jersey obtained cell phone subscriber information 79 times between 2002 and 2008 without seeking a warrant.
Giving law enforcement free rein opens up broad opportunities for information gathering on people who aren't even necessarily persons of interest in an investigation, says Granick.
"One example would be that police could find out the names of everyone who was near a political protest site just because they were investigating someone or something that happened there," she says.
At press time, a federal appeals court was set to hear arguments in the New Jersey case. How the court rules may determine how much of a snoop your phone continues to be.
The Fix: If your handset has a GPS chip and you don't want to be tracked, turn it off. Even then, the carrier may be able to ping your phone to determine the cell towers nearest you. Turning off your phone entirely is your best bet for dropping off the grid, if only temporarily. The next time you use your handset, though, you'll be back on your carrier's grid.
A 'Cheap' Smartphone Is a Rip-Off
Your wireless company might like you to think that your handset is locked to one carrier for myriad technical reasons, but there's really only one reason: profits. The carrier wants to lock you into paying hundreds of dollars a month for mobile voice and data service, and to accomplish that it will sell you a subsidized smartphone for much less than the company paid for it.
Spending more up front for an unsubsidized phone, however, might save you money in the long run. PCWorld contributing editor JR Raphael compared the fees for an unsubsidized $529 Nexus One phone (and an à la carte contract with T-Mobile) with those for the iPhone 3GS and the Motorola Droid, which are available only with a two-year contract (from AT&T and Verizon, respectively). The cost savings over two years: $1350, thanks largely to T-Mobile's $80-per-month unlimited voice, text, and data plan (no contract required).
It gets better. Ben Ferguson, on his Nosugrefneb blog, compared a subsidized $295 Nexus One plus a two-year T-Mobile plan with an unsubsidized model using a $40 T-Mobile data plan and a $3-per-month VoIP account on Skype. Using the data plan and VoIP lopped an additional $482 off the cost--making that option $1800 cheaper than a subsidized iPhone.
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