I think there is some confusion over the different technologies. GPS is different from the service offered by Verizon. It has now been about 5 years since all cellular phone providers have been forced to record the geographical position of any cell phone when a call is made within their network. It does this by picking up the microwave radio transmission from the phone to multiple towers, computes the time delays for each tower then performs a calculation to compute the geographical position of that radio transmission (the computation takes into account the geographical position of each tower and the geographic radio transmission mapping). Accuracy was initially about 100m in the year 2000. As the computational models improved accuracy has improved to around 10-20m within the cell network. Every cellular service provider has the ability to record every call made together with the geographical position of that call in the US and is mandated by law to do so. Everyones cell phone in the US and in the UK has the ability to be tracked and monitored. I always have a little chuckle at the terrorist in the TV show '24' using a cell phone to carry out his dastardly plan. Cell phone networks also have other abilities too. Stealth Aircraft can be easily detected as the aircraft passes over the cell network from the hundreds of cell towers each working as RADARs. The service offered by Verizon will only work within the Verizon cell network. GPS uses a network of Satellites that circle the planet. GPS works by the box of electronics in your hand doing the positional computation from the Satellite broadcast transmissions. The Verizon systems works the opposite way around and Verizon can track your every movement within the cell network. Verison holds this positional information, not the cell phone itself. The GPS system cannot do this, it cannot track your position. Most people who own cell phones are unaware that their cell phone can be tracked geographically which is why some assume there is something called a GPS circuit and antenna built into their phone. The phone companies don't want to correct that incorrect notion.