Those with web-enabled devices are 1.5 times more likely to be sexually active than those without.
The University of Southern California claims high school teenagers with smartphones are more likely to have unprotected sex than those in possession of a less able device.
Even more worryingly than the chances of STIs and pregnancies they're opening themselves up to, is that the encounter is twice more likely to be with a random met on the web.
The data shows 17 per cent of smartphone-using teens were approached for sex online by someone they didn't know, twice the figure of those without a smartphone.
The report also claims the smartphone owners are 1.5 times more likely to be sexually active than peers using feature phones.
Device types weren't specified, but a past report suggested Android users are more likely to put out.
Meanwhile, a recent app called Knocked App gave the appearance teenagers were pregnant, which caused uproar from family planning groups.