I was also going to say about the phone batteries catching fire but was beaten to it by Mojo-Chan. I was told by the Captain of a plane I flew on that the real reason they don't want people using phones on planes is due to the explosion risk apparently particularly high at disembarkation due to the kerosene vapors hanging around the plane after landing, if a phone is dropped from the plane as a passenger leaves and lands on the concrete the battery can burst and explode, I expect that the use of covered walkways has reduced this risk hence the drop of the phone ban.