The organisation's survey also revealed that 35 percent of kids with mobiles say their parents don't know they use it to access the Internet.
Save the Children has long advocated stricter parental supervision of their kids' Internet use. They worry that the portable web phenomena will make more children susceptible to Internet predators.
Their poll shows that more youth are sending pictures taken with their mobiles, even to people they've only met online.
Nearly 18,000 youth between the ages of 7 and 15 responded to the survey.