Thanks, KISS,
I looked at that. It's good but not exactly user friendly!
This is helpful also.
But Wikipedia does say that under 100 meters is "very high accuracy." Well, that's 328 feet. We have a guy in the relationships thread who thinks his wife is cheating on him because the iPhone she's carrying says she was on the other side of a street and up an alley instead of in front of his house (when she says she was walking home). Obviously, he's nuts. But aside from that, what I'm trying to get at is, in real use, instead of just theoretical discussions, what does phone tracking really tell the tracker?
Worst case, I get that it can be off by 35 km or in rural areas. In contrast, in dense urban areas where there are hardly any tall buildings and there are lots of cell towers, even cell triangulation can be pretty accurate (< 100 m). But why does a phone seem very accurate one day, putting you in the right room of your house, and then put you half a mile off the next day?
I know that buildings, trees, and hills can affect the accuracy in both gps and triangulation, but what else affects the readout and how MUCH do they affect it, and why in each case?
Gps is supposed to be more accurate, but when I read around, I'm seeing the same 100 m figure quoted for both gps and triangulation (in urban areas). How much more accurate is gps than cell triangulation in a big city where there are lots of towers? And, in a given area on a given phone, what's the best you could count on on a regular basis? 50 feet? 25 feet? I'm not counting the occasional reading that seems to put you in your own bathroom but can't replicate that accuracy. It has to be consistent or it doesn't count as information you "know." Hope that makes sense.
How can I explain to someone like this guy that he doesn't know what he thinks he knows?