Toddlers are becoming so addicted to iPads and smartphones that they require therapy, experts have warned.
A guide to how to turn off in-app purchases on an iPad to avoid potentially running up expensive costs.
A five-year-old boy has racked up a £1,700 bill in just a few minutes by unwittingly buying add-ons for a zombie game on his parents' iPad.
The Office of Fair Trading has launched an investigation into games on phones and tablets that are free to download, but could end up costing parents hundreds - even thousands - of pounds.
It follows concerns that children could be tricked into spending money on upgrades without realising the cost.
Justin Cooke, from the British Interactive Media Association, told ITV News that the games industry did not need more regulation and that self-regulation was working.
"No doubt, there needs to be some changes to reflect the massive change going on in our industry," he said.
"Things like, for example, putting in place instant notification of payments being made through in-app."
"I think parents need to take some responsibility in the same way that I wouldn't give my kids the PIN number for my credit card," he added.
In March, a mother warned other parents about the dangers of free download games after her six-year-old daughter ran up a £900 bill on her iPad - without even needing her iTunes password.
Grace Walker from Cheshire was able to click and buy "virtual gems" to boost her performance in a My Little Pony game at £69.99 a time - running up a bill of over £900 in just 30 minutes.
Internet and mobile phone games which are free to download are being investigated by the Office of Fair Trading.
It follows concerns that children could be tricked into spending money on upgrades, Daybreak's Jonathan Swain reports.
– Which? executive director Richard Lloyd
It's far too easy for children to run up huge bills on phone apps when most default settings allow 'in-app purchases' without asking for a confirmation or password.
Parents who want to stop this should either turn off the default setting or switch on parental controls so that passwords are required for any in-app purchases.
If your child has run up a huge bill without your knowledge, contact the app store or manufacturer as you may be eligible for a refund.
The OFT said it is investigating a number of "free" web and app-based games with concerns over additional costs from add-on features.
In March, ITV News spoke to Danny Kitchen and his mother Sharon. Danny racked up a £1,700 bill in just a few minutes by unwittingly buying add-ons for a zombie game on his parents' iPad.
Martin Lewis, the founder of MoneySavingExpert.com, said it was "disappointing" that apps aimed at children have been allowed to charge "ridiculous amounts" for extra features. He said:
When games such as My Little Pony, which are obviously targeted at young children, bait kids with 69p purchases of a 'mountain of gems', something is going wrong in the system.
What's really disappointing is it's been allowed to get this far. Apple especially makes a play of only allowing approved apps in its store.
So why does it allow games that can be targeted at young children to charge such ridiculous amounts for in-app purchases?
As always, an OFT investigation, even if it does advise action, will take time. So the most important message meanwhile is to protect yourself.
The OFT said they are concerned that children and parents are subject to "unfair pressure" to purchase, when playing on web or app based games, which can lead to "substantial costs".
– Cavendish Elithorn, OFT senior director for goods and consumer
The OFT is not seeking to ban in-game purchases, but the games industry must ensure it is complying with the relevant regulations so that children are protected. We are speaking to the industry and will take enforcement action if necessary.