This chart courtesy of eMarketer.com.
Is Line losing its place atop Japan’s social scene? June 2015 research from JustSystems found that seven in 10 internet users in Japan used YouTube—more than 24 percentage points ahead of second-place Line.
Earlier research has shown Line is far bigger in Japan than Facebook or Twitter—but those surveys didn’t ask about YouTube usage. One that did, taken by Japan’s Ministry of Internal Affairs and Communications (MIC) in November 2014, also found that YouTube was the most popular social media service in the country, with 65.1% penetration of internet users. Line was in second place, at 55.1%.
In the JustSystems research, Facebook and Twitter continued to lag YouTube and Line, and no other social media service reached more than one in five internet users.