What will happen if I take my child's phone away?

For three months last year, Karly held firm. Within six weeks she noticed a difference. Dylan’s marks improved. He became more talkative, more energetic. He started wanting to go outside again and play with his little brother.

He now had so much spare time on his hands and was so much more engaged with his family that he offered to help his mother with chores. As Karly pointed out: “It’s been a great decision for us – I’d call on others to follow.”

But of course, many parents reading those words will still be hearing a voice in their heads whispering: “Easier said than done.” And while the consensus is that children using smartphones as their default entertainment is not a good thing, there’s still no general agreement on what should be done.

Over the past 10 years, kids’ screen time has crept up relentlessly. According to figures from the tech industry’s advice body Internet Matters, children between 11 and 16 post online an average of 26 times a day. Even when adults impose daily limits, eight out of 10 children admit they flout them.

Furthermore, a recent report from digital advice group Common Sense Media found that half of teens now feel “addicted” to their mobile devices – and 60 per cent of parents agree with them. The result is “daily conflict” over phone use.

So given that smartphones are fundamentally changing the nature of family life, why can’t we all agree what to do?

Psychologist Dr Aric Sigman believes parents would find it easier to take action if we reframed the way we think about smartphones.

“First of all, smartphone is a dumb word. They are not phones. They are high-powered computers, far more powerful than even laptops were 10 years ago,” he says. Beyond that, Dr Sigman believes parents will find the resolve to place limits on kids’ phone use if they start looking at the matter “not as a lifestyle choice, but as straightforward medical issue”.

One of the key limits he believes parents should introduce is a “digital sunset” in which children’s devices are removed between one and two hours before bedtime.

“Bedrooms should be sensory deprivation zones,” he says, “but phones make them entertainment centres. There is a clear link between the use of these devices at night and sleep deprivation.

“Late-night use has been linked to depression, anxiety, lower school grades and increased body fat because a deficit of sleep seems to alter hunger hormones.”

But while a total ban on devices may sometimes seem the only solution to an exasperated parent, parenting educator Noël Janis-Norton says it does not have to be an all-or-nothing approach.

She agrees with Karly’s idea that one phone-free day a week is a good start – even if your child does bitterly protest.

Ms Janis-Norton, author of Calmer, Happier, Easier Screen Time, says: “Children may complain they’ll lose their social lives but it’s just not true. They have friends for lots of reasons and their accessibility to social media is just one factor.

The other things parents will say is that they don’t want to upset their children. But there are lots of things that parents have to do because it’s the right thing to do.”

Dr Sigman believes children need to be taught to recognise the symptoms of smartphone over use – whether it’s eye strain or irritability. “It should be one of the many health issues parents speak to children about,” he says.

“Parents have got to say, 'It’s not that I don’t want you on social networks. But your social life should also be happening in the real world and the constant culture of comparison and bitchiness on these networks could make you unhappy.’ ”

Indeed, after a three-month break from his phone, Dylan admitted he welcomed a rest from the pressure of having to respond to constant notifications, saying: “I was upset at the start but it’s not actually bad. It gives me more time to do other things.”

Tanith Carey is the author of Girls Uninterrupted: Steps for Building Stronger Girls in a Challenging World