RE: GPS in Smart Phones
AFIK all smart phones have a GPS receiver that is usable by the owner.  An
even without the GPS turned on yes, they will give an approximate location
based on the cell phone towers.  BUT if no cell phone towers in range that
can't work.  That's when the GPS will work.  The problem with using most of
the GPS based mapping and driving directions applications on the smart
phones is that they depend on a data connection to download the map data.
No cell or data connections mean they don't work.  That's where the
dedicated GPS receiver beats them (not counting much better software and
user interface) because the map data is stored in the GPS unit, no need for
an Internet connection.