Christopher Nolan, the award-winning film director, recently made a startling admission: he does not own a mobile phone. Neither does Nolan, whose work includes the Dark Knight trilogy, Inception and Interstellar, ever use email. He doesn’t even have an account. “It gives me time to think”, the 44-year-old says. “You know, when you have a smartphone and ten minutes to spare, you go on it and you start looking at stuff.” Yes, yes you do. No doubt about that.

Sit in any restaurant and you’ll see that one half of a couple can’t even nip to the toilet without the other feverishly reaching for their phone to check Twitter or Facebook (guilty). The notion of simply waiting until they come back, maybe taking in