With the latest revelation that Oscar Pistorius used his cellphone to watch porn just hours before shooting dead his girlfriend, Reeva Steenkamp, the issue has been thrust back into the spotlight.
In November 2011, the cellphone industry's self-regulating body reported that at least 90% of children aged between eight and 16 with internet access have viewed porn online – often by mistake.
In their annual review for 2013, online porn giant Pornhub revealed that 40% of their traffic comes from mobile devices.
The fact that Pistorius viewed the material so close to the murder is being used as one point of the state's complex case against him. They believe that it does not fit with the behaviour of a couple who were deeply in love, as Pistorius has professed they were in his defence.
It said that 22% of teen girls and 20% of boys had sent inappropriate photographs of themselves via SMS, which were finding their way on to porn sites.
Russel Stromin, head of the Code of Conduct Committee for the Wireless Application Service Providers' Association, said children had easy access to mobile devices, such as cellphones with the internet. This meant the number of children viewing and sending inappropriate material was widespread.
"As the industry body for the mobile applications industry, we encourage our members to provide parents with tools to protect their children," said Stromin.
Parents can block cellphones
This could mean blocking access to adult sites on a child's cellphone, but also talking to children and warning them, Stromin said.
All cellular providers could block access to specific sites, he said, while illegal sites could be blocked for everybody.
"Parents can dial their provider's customer service number and request the site to be blocked."
Protecting young people
Mobile phones were increasingly being used to solicit youth aged 12 to 25, and protecting young people had to become a priority.
"Globally, mobile service providers have taken the lead in this area, with the mobile alliance against child sexual abuse content being launched at the Mobile World Congress in Barcelona in 2008," Stromin said.
"Blocking your children's cellphones from accessing adult content is a good start, but it's only the beginning of what parents need to do."
(Sapa, September 2011. Updated February 2014)
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