Find my iPhone is completely useless if the device is not connected to the internet via 3G or Wifi. However the iPhone has GPS which does not require either any connection, when I open Maps without Internet connection it still finds my position, even though the map is grey and I cannot see anything. Since I'm using a computer with an Internet connection to find my iPhone, why I cannot use the GPS signal of my iPhone and the internet connection of my computer to locate its position?