And they are free to do so because the GPS units pose no risk to the aircraft, just as I use my iPad or smartphone on a plane. Once you start talking about tra

And they are free to do so because the GPS units pose no risk to the aircraft, just as I use my iPad or smartphone on a plane. Once you start talking about tracking systems that are tied into the plane's avionics in order to deliver information about the aircraft itself, that's another story.