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 Tumblr Tests New Tools for Users and Brands Can the Company Be a Business Without Traditional Advertising? Founder David Karp Explains By David Teicher, Published on April 12, 2012 2 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. Become a Member Already a member? Log in.