Eugen Leitl <eugen@leitl.org> wrote:
Jamming GPS is no problem, but then they'll just triangulate you within the cell. The only way to prevent that would be to switch off, andn to pull the battery (unless the firmware is open source, and peer-reviewed).
A little poking around on google reveals that all but the most recent Sprint phones don't support GPS at all. They rely for location on AFLT, advanced forward link trilateration. That is, they look for multiple towers, then report their delay readings to the network, allowing triangulation. More recent phones from Sprint must support real GPS, since Qualcomm offers chipsets with GPS support, which they wouldn't do unless their only customers (Sprint phone manufacturers) wanted it. -- Riad S. Wahby rsw@jfet.org