There is little evidence screen use for children is harmful in itself, guidance from leading paediatricians says.
Parents should worry less as long as they have gone through a checklist on the effect of screen time on their child, it says.
While the guidance avoids setting screen time limits, it recommends not using them in the hour before bedtime.
Experts say it is important that the use of devices does not replace sleep, exercising and time with family.
It was informed by a review of evidence published at the same time in the BMJ Open medical journal, and follows a debate around whether youngsters should have time on devices restricted.
Meanwhile, a separate study has found that girls are twice as likely to show signs of depressive symptoms linked to social media use at age 14 compared with boys.
'No evidence of being toxic'
The Royal College of Paediatrics and Child Health (RCPCH), which oversees the training of specialists in child medicine, has produced the guidance for under-18s.
It said there was no good evidence that time in front of a screen is "toxic" to health, as is sometimes claimed.
The review of evidence found associations between higher screen use and obesity and depression.
But the college looked at this and said it was not clear from the evidence if higher screen use was causing these problems or if people with these issues were more likely to spend more time on screens.
The review was carried out by experts at University College London, including RCPCH president Prof Russell Viner.
The college said it was not setting time limits for children because there was not enough evidence that screen time was harmful to child health at any age.
Instead, it has published a series of questions to help families make decisions about their screen time use:
Is your family's screen time under control?
Does screen use interfere with what your family want to do?
Does screen use interfere with sleep?
Are you able to control snacking during screen time?
Dr Max Davie, officer for health promotion for the RCPCH, said phones, computers and tablets were a "great way to explore the world", but parents were often made to feel that there was something "indefinably wrong" about them.
He said: "We want to cut through that and say 'actually if you're doing OK and you've answered these questions of yourselves and you're happy, get on and live your life and stop worrying'.
"But if there are problems and you're having difficulties, screen time can be a contributing factor."
Dr Russell Viner, president of the RCPCH, told BBC Radio 4's Today programme "screens are part of modern life", adding: "The genie is out of the bottle - we cannot put it back."
He said: "We need to stick to advising parents to do what they do well, which is to balance the risks and benefits.
"One size doesn't fit all, parents need to think about what's useful and helpful for their child."
Parents should consider their own use of screens, if screen time is controlled in their family, and if excessive use is affecting their child's development and everyday life, he added.