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 Study: Mobile Marketing Industry to Employ 1.4 Million In 2015 Return on Mobile Advertising Will Drop As Lower Income Consumers Adopt Smartphones By John McDermott, Published on May 09, 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.