A report says the rise of online social networking tools such as MySpace has exposed children to dangers such as cyberbullying, grooming and fraud - especially in connection with mobile phones.

The findings, featured in a report commissioned by Garlik , showed that 20 per cent of the 8- to 15-year-olds surveyed had given out their mobile numbers online.

Although the potential dangers of PC based internet use for children are well understood, AdaptiveMobile 's Lorcan Burke argues that when it comes to mobile phones there is still a lot to learn.

"While the internet is generally accessed at home via the family or individual child's PC, how many parents think about the access their child may have via their personal mobile phone?

"Although not immediately obvious, the mobile phone poses a more serious problem than PCs as they are an inherently more private medium and are harder to police."