Hi Guys,
All electronic devices be it a GPS or a mobile phone transmit energy once switched on. The difference the amount of energy that the device emits. A battery-powered handheld GPS will give out very little energy and is likely to affect nothing, while something like a Laptop emits a lot more energy (try using a portable music radio right next to the computer).
Mobile phones when switched on periodically transmit a signal for a few seconds, the reasons for which I have no idea, but this can affect other electrical systems and must be switched off on board.
If the GPS is designed for aviation use in the cockpit, then using it in the pax cabin should be fine too. Though I woulden't say to go against anything the cabin crew tell you. Best do what RUDAS did and check with FD first.
This is the situation as far as I understand it.
Cheers, Tri
