Why you should give your child a dumbphone if you want them to be smarter

Research shows being a high user of apps can significantly reduces your grades. Photograph: Drazen Zigic/Getty Images

First, the good news. We middle-aged Brits are no longer condemned to the conversation- and soul-destroying monomania of debating house prices.

Less good is what has displaced it – an epidemic of angst about when to allow teenagers a mobile, and what kind. I’m in the “very late and a brick” camp, but parents end up discussing the options for a smartphone-free childhood, inevitably, on WhatsApp.