You’ve read all of your free items this month. To register, get added benefits and unlimited access to articles, Become a Member. Already a Member? Sign in. Advertising Age Article Abstract From Japan, The Biggest Social Network You Never Heard Of 'Line' Has Gone Viral With Consumers, Fueled by Ads and Stiff Fees for Business By John Stampfel, Published on June 14, 2013 4 Want more Access, Content & Connections? Upgrade to Membership. We are glad you are enjoying Advertising Age. To get uninterrupted access and additional benefits, become a member today. Register Now Already a member? Log in.