The figures from the UK show schoolkids aged between five and 15 are online for about 15 hours each week
Children are now spending longer online than they do watching TV for the first time, according to new figures from the UK.
On average, schoolkids aged between five and 15 years old are online for about 15 hours each week - an hour and 18 minutes more than last year.
Viewing times of traditional television tumbled to 13 hours and 36 minutes a week - a decrease of an hour and 14 minutes.
OFCOM says YouTube has become one of the most popular online destinations for children to watch content.
Its research suggests 73% of five to 15-year-olds and 37% of pre-schoolers use the video site regularly, often to watch TV-style cartoons and mini-movies.
Despite this, 90% of children still generally tend to watch TV every day between 6pm and 9pm.
Whereas tablets are more popular among children of a pre-school age, most begin to prefer mobiles as they get older - and now it is estimated that about 33% of eight to 11-year-olds have a smartphone of their own, rising to 80% of 12 to 15-year-olds.
Although technology is playing a bigger role in young people's lives, two-thirds of parents with children aged between 12 and 15 believe their child has a "good balance" between screen time and other activities.
A separate piece of OFCOM research shows reading remains the third most-popular activity among children of a primary school age - well ahead of watching music videos and online video clips.
Jane Rumble, the regulator's director of market intelligence, said: "Children's lives are increasingly digital, with tablets and smartphones commanding more attention than ever.
"Even so, families are finding time for more traditional activities, such as watching TV together or reading a bedtime story."