YOUNGSTERS are spending up to seven hours a day glued to their smartphones, figures reveal.
An Ofcom study shows nearly a fifth of 16 to 24-year-olds are online for that time.
Three-quarters spend the equivalent of two days a week on their phones, and a third at least 40 hours.
Young women are more addicted than young men, stuck to their mobiles for an hour a day longer on average.
Yet the Ofcom research also showed that adults are spending increasing amounts of time on their phones and other devices, with four times as many online for more than 40 hours a week than in 2007, when the iPhone was released.
Youngsters admit they are more productive when they are cut off from the internet, and more than half say devices interrupted time with family and friends.
Tanya Goodin, founder of the digital health consultancy Time to Log Off, hopes the results will give youngsters a wake-up call.
She said: “It’s not just affecting people’s relationships and productivity but also mental health.”