The Times' thoughtful columnist James Marriott writes - and hopes, I think - that he can imagine a time when social status, rather than bans, will get people off their smartphones.

"Economically at least, smartphone dependency is a sign of low status," he writes - and because humans are finely attuned to the nuances of how people think of us, often considering it more than our health, it will be stigma, being perceived as having to be on one's phone, that gets one off it.