Not many companies advise customers to use their most popular products less. Yet Craig Federighi, Apple’s head of software engineering, spoke in a hushed voice in California on Monday about how use of the iPhone had turned into “such a habit that we might not even recognise how distracted we’ve become”.

Even fewer of them suggest ways of taking a break when their market has run out of growth, as smartphone unit sales have done. Eleven years after the iPhone’s launch, global sales of the devices fell slightly in 2017 and IDC, the research group, expects another fall this year. It does not seem the ideal time to list the product’s evils.

Apple is not too worried. Any company that devotes so much of a two-hour presentation to playing with MeMoji cartoon avatars, demonstrating an app that mimics a two-way radio and showing an augmented reality Lego set cannot feel in existential danger. “You’re going to love those aerial screensavers!” Tim Cook, Apple’s chief executive, exclaimed to app developers.