This is probably a stupid question, but I haven’t been able to find a definitive answer yet. Let’s say you are kidnapped and your abductor doesn’t realize that you have a cell phone hidden in your pocket. The cell phone is turned on, but you can’t make a call without being noticed. If law enforcement was aware that you had a cell phone somewhere on your body could they or the phone company somehow track your whereabouts anyway?
In other words, can someone pinpoint your location by the fact that your cell phone is on without you having to make a call? Would your phone have to possess a GPS chip or is that irrelevent?
The last phone I had before my Helio was a Sanyo phone on the Sprint network. Some friends and I had gone walking around the city late one night, and we returned to one of my friend’s apartments. I realized that I didn’t have my cell on me anymore, and I know I had it earlier in the night after we had started walking.
I went on to Sprint’s website and found a tool like the one you describe. It cost something to the order of $9.99/month (which I gladly paid one month’s worth to use), and within a minute, I had a zoomed map of the downtown area on my screen. I believe it had a margin of error of a few dozen feet, but a quick walk back found my phone exactly where the map showed it – sitting on a bench.
ETA-- Found it. Sprint Family Locator. For the service, you need a GPS-enabled phone, it has to be on, and on the Sprint network (ie: not roaming). I’m sure other carriers have something similar.
More specifically it can be determined which cell tower is receiving the strongest signal from the phone; not sure where your radius comes from but cell size can vary.
One last question. Let’s say I was abducted a few hours ago and that I have been driven out into the woods where there is no cell phone coverage. Would someone still be able to see where I was during the day so they could trace my travel before I was out of range?
In other words, does the phone company store data on my location through the day or is it just real time information?
Not actually triangulated, since it is only using one tower rather than three. It’s possible that your phone could receive from 3 towers, but it would pick the one with the strongest signal and reply to that one.
Possibly the police could look at the history of which towers your phone had been responding to, and trace the route that way – they might determine that you were traveling southbound on freeway I-35, for example, and that would help them set up roadblocks or something.
If it helps the discussion, I have an app for my iPhone called “Locate Me” which scans the towers around, and it isn’t unusual to see 6 or 7 towers connected, but when it tells you your location (which is only accurate to a quarter-mile or so, I’ve found) it tells you how many towers it’s using to calculate it, but it seems to max out at 3.
