Paraphrashing from an article in a recent PC Magazine:
Most new cell phones have GPS receivers built in, but the carriers have not necessarily activated them.
Expect phones to become increasingly location-aware, thanks to the federally-mandated E911 legislation, which requires cell phones to be physically locatable in case of emergency.
Someone called uLocate is offering location service to fleet operators and parents. Subscribers can set up “geofences” surrounding schools, the bad side of town, etc. and message you if the monitored phone enters or leaves that area. Location data is retained for 90 days, providing an “audit trail” of where that phone has been.
Uh, are you sure about this? GPS recievers have highly accurate clocks inside them that cost at least $50 to manufactur. I doubt cell phone makers are sticking working but de-activated ones in cheapass phones.
If you have a GSM net in town you use a Compaq PDA with GPS and GSM chips inserted. You program the PDA to read the GPS unit and send the coordinates via the GSM network as a simple text message.
On the receiver side you use a lap-top with a displayed map and a set of cross-hairs that correspond to the lat-long received.
Problems with this technique are:
Tracking multiple cars. Your phone line may be become jammed if you set the update period too short.
The phone bill can get big, but then James Bond never worries about his bills anyway.
We’ve done this a few times and it works well enough.
The software company that I recently worked for developed software that allowed a company to track all the vehicles in the fleet pretty accurately, by interfacing with GPS.