About 60 per cent of parents who allow their children to have a smartphone are worried about their children becoming addicted to the mobile device, according to a survey conducted by the Tokyo metropolitan government.
Despite this, the ratio of parents who subscribe to mobile phone filtering services to prevent children from accessing harmful websites stood at only about 30 per cent, the survey said.
The metropolitan government conducted an online survey in December on 1,500 parents in Tokyo who allow their children - in the bracket from fourth-year primary school students to third-year high school students - to have smartphones and other kinds of mobile phones.
When asked in the multiple-response questionnaire what worried them about letting children use smartphones, 63.3 per cent of the 791 respondents who said they gave smartphones to their children said that children may become addicted to smartphones.
Meanwhile, 47.3 per cent said the children may get into trouble with friends by using social networking services, and 37.9 per cent said they may meet strangers through dating applications.
While the overall ratio of those who subscribe to a filtering service stood at 31.9 per cent, and the ratio of parents of primary school students was 22.8 per cent, 43.4 per cent employed settings to prevent connections to the Internet or selected mobile phone models that are unable to access to the Internet.
The percentage of middle school students whose phones were subscribed to filtering services was higher than those who do not, but for high school students the opposite was true.
Meanwhile, the overall ratio of households that make rules for using smartphones was 58.1 per cent.
The rate of households making such rules for primary students stood at 61.2 per cent, middle school students at 69.2 per cent and high school students at 43.8 per cent.
When asked about the rules, 51 per cent said they limit online hours, 47 per cent specified manners for using mobile phones and 41.6 per cent limited the websites children were allowed to access.
"It's important to educate primary and middle school students at an early stage about the detrimental effect of harmful websites, and make rules about using the Internet at each household," an official of the metropolitan government said.