Someskeptics havepointed out that, even ifshetraveled back in time with her phone, she couldn't have been talking into it because there were nocellulartowers back then.
The problem with femtocells until now, Cooper noted, has been interference between local base stations and faraway cellulartowers when the two sources broadcast to a phone simultaneously.
Nope, instead your phone has been tracking information about its location in relation to wi-fi hot spots and cellulartowers so it can figure out where it is.