No it doesn't. GPS requires the interaction of satellites, which do not connect with mobile phones (unless satellite phones, of course - and there are few of them around!). All mobile calls can be traced to within a radius, however that depends upon the numberof cells that are in contact with the phone. Cellular communications are so called beciase the radio system id split into cless. each with a transmitter/receiver. The morfe of these that a phone is in contact with the more accurate will be the location of the phone. If you are out in a rural area this may be only one cell, so you may be anywhere in that area. So the story you have heard is just that - a story. Also the number you dial is of no consequence, simply the swithcing the phone on is all that is required. HAving dialled an emergency number can alert the services to take the location actions, nothing at all to do with the number you dialled, just the person you ended up speakingt o taking action and as 999 and 112 both connect tot he same system neither is actually any different.