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 Putting a Tag on Everything That Moves at SXSW The Mobile Tag Is Quickly Replacing the URL in Marketing Communications By Erin Jo Richey, Published on March 15, 2011 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. Become a Member Already a member? Log in.