iPad and smartphone use among youngsters is being blamed for a 9 per cent rise in the number of Perth children needing expert help with speech and language problems over the past two years.
More than 6200 children were referred for speech pathology treatment last year and another 1100 youngsters with severe language problems attended full-time specialist centres.
Speech therapists warn they are seeing more children failing to develop basic language skills, partly because they are spending hours glued to screens instead of conversing.
Therapists say iPads, iPhones and other screen-based technology are being used as "electronic babysitters".
Rosie Candler, from the Private Speech Pathologists Association of WA, said she had noticed a huge change, with children as young as 18 months now coming to her clinic for treatment.
"They turn the iPhone on and they turn off," she said.
"Children are missing everything around them."
A total of 6263 children were referred to the 11 child development centres in the metropolitan area last year, almost 9 per cent more than the 5756 children in 2010.
A child and adolescent health services spokeswoman said a jump in the rate of speech and language difficulties and the rapid rise in the State's population were factors behind the rise in referrals.
More than 20 per cent of WA Year 1 schoolchildren were deemed "developmentally at risk" in language and cognitive skills in the Australian Early Childhood Development Index, the second highest nationally after Queensland and twice that in NSW, Victoria, South Australia and the ACT.
Even worse, 12 per cent of children were rated as "developmentally vulnerable" and did not have most of the basic literacy skills, with problems identifying letters and sounds.
"It's a growing problem with the changing times," WA Primary Principals Association president Steve Breen said.
"The consequences are the children are severely delayed."
The association said children could wait up to two years to see a speech therapist in metropolitan Perth. But the Department of Child and Adolescent Health Services said there were indications a recent cash injection had cut waiting times significantly.
Ms Candler, who has worked with children for 33 years, said children were playing less with games requiring interaction or discussion with others.
Ms Candler said television, iPads and other screen-based technology benefited children if their use was supervised and controlled.