I'm looking for a remote GPS solution and found this out about phones, and one of the Best Buy guys just said that tables usually use the most recent Wi-Fi spot and then it tracks you from there.
This is what I came across so far, in my research on this - --- Hope it helps. I'm thinking of a Table and then use a GPS attachment. I used to work in the field, Telecom work and used MS Streets and Trips, it had a GPS/USB adapter that plugged in that used (real) GPS.
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You turn on your mobile phone in an area with cellular service. The low power GPS chip gets a
hint from the cellphone towers as to where it is, effectively narrowing down the possibilities
from "anywhere on earth" to within a few mile radius. With that huge hint the GPS chip doesn't
need to search as hard to figure out where you are. Now you drive out of cell coverage. No huge
worry as the GPS will have been keeping up with your location and it will use that to figure
keep up.
Second scenario... You turn on your mobile phone outside of an area with cellular service and
to add problems your phone is hundreds of miles away from where it last had a GPS fix. In this
scenario, without a hint from the cell towers and having tried to figure out where you were from
the last known position the GPS chipset is on its own to figure out where you are. With a weaker
receiver capability than a dedicated GPS chip it will take a very long time to figure out where
you are from this "cold" start. And if you have an obstructed space view it is possible you
could fully deplete a battery before it finds you