Originally Posted by janeway
Do any of you know why the rule to turn off electronic devices at take-off and landing actually exists?
All electronic devices generate electro-magnetic interference. Some very little; others a lot. The concern is that the interference could interfere with electronic aircraft systems, which is most critical during take-off and landing.
The electronic systems on the aircraft (e.g., aircraft audio system) have been tested for interference, but your personal device obviously has not been tested by the airline or FAA.
Under FAA regs, an electronic device can only be used during take-off and landing if it is certified as not producing interfering levels of electro-magnetic interference.