Well if a handheld is 'aviation' approved then it should work just fine on an airliner? Right?
If a GPS just receives signals, how could it interfere with the Aircraft systems? Just the same as my little cd player doesnt affect anything!
True that tests were done proving that there is sometimes interference, but on the in the case of hundreds of laptops and radios and cd players being used in specific locations near the flight deck all at the same time. Or so I am told anyways.
-Chris