Well, most of the stand alone GPS devices are nothing to worry about as they are only passive receivers and do not have the ability to transmit. However, cell phones are a different story as they are always transmitting a signal that locates the user. It is a part of how cellular networks function. In fact, most cellular GPS is not really GPS in the sense that it operates off of a satellite network. No, cellular GPS operates off of cell towers just like the phones, and is used as a byproduct of the phone system itself as a value added feature. Remember that whether you have a GPS enabled phone or not, you can be tracked by it as long as it is turned on. If you remember the OJ Simpson low speed Bronco chase, that is how the police located him. They triangulated his passive cell phone signal-and that was in 1994.