> The phones do not have actual GPS receivers
> built-in: it's some funny business with cell tower signals, and they
> call it "GPS".

I don't know the specifics of cell phone use, but I'm imagine it's
similar to LORAN navigation. (http://en.wikipedia.org/wiki/LORAN)

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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