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 Brands Get a Boost by Opening Up APIs to Outside Developers From Best Buy to Tesco, Marketers Are Gaining Useful Apps and Services by Making Data Public By Abbey Klaassen, Published on November 30, 2009 3 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.