I only ask because I constantly see people ignore this rule. On a recent flight, the guy across the aisle and one row ahead of me was trying to make phone calls while the plane was taking off. On my way home from the trip, the guy next to me was texting photos to his wife while the plane was descending and about to land. These were 100% SMS messages and phone calls on mobile data - not Whatsapp or another messaging service that can be used on wifi.

I want to tell these people to knock it off because I always thought it was a safety issue. But it seems to happen so often without consequence that I just ignore it. (And I saw these guys doing it, but I'm sure plenty of other people on the plane were also doing it too.) Should people really be shutting off their phones or turning them to airplane mode? If not, then why are we asked to do that?