More teens are on YouTube than any other social network, according to research from the National Cyber Security Alliance and Microsoft. Their poll of 13-17-year-old internet users found that 91% say they use YouTube, compared to 66% who use Snapchat, 65% who use Instagram, and 61% who use Facebook. Their heavy use of the site is one of the reasons that YouTube stars have more influence over teen purchase intent than traditional TV and movie celebs. Interestingly, the second most-used platform was actually Gmail, with 75% of teens reporting they use the email app.