Re: Cell phone tracking

Carlos E.R. wrote:

D wrote:

Anonymous  <nobody@yamn.paranoici.org> wrote:

I just heard an engineer describing how phones are doing something new

now in tracking people.  Some phones today (probably android and apple)
are continuing to track you after you turn the phone off and store the
data on your phone.  When you turn them back on, the phone then sends
the tracking data to a server.  The only way to defeat this is to put
your phone into a faraday bag, most that don't work.

 This is ridiculous.

For the moment agree, but there's a grain of truth behind it ... There have always been the tin-foil hat brigade, who claim phones are never really "off", but these days that's actually true for certain phones.
In the name of making lost devices findable, the last act of turning a phone "off" or the battery getting low, is that is notes its location, pre-generates some beacon frames with (encrypted?) details of its id and location, then it activates a low power background CPU which periodically wakes up, and transmits those beacons over bluetooth, in the hope that a passing device hears them, and forwards them to the mothership.
Now, I don't claim that this background activity is actively gathering location info while off, but we're no longer a million miles from that, and "off" no longer means literally off ...