Dallas-Fort Worth International Airport (DFW) is one of the nation's busiest airports, with nearly 160,000 people passing through each day. To make matters worse for harried travelers, DFW will be undergoing construction for the next 18 months.So CIO William Flowers is eager to make it easier for customers to navigate the airport's five massive terminals. "A guide system and information about our services we felt would be a necessity," he says. With 85 percent of its travelers using smartphones, DFW developed a mobile app to help them find their gate, some food and a parking spot.Flowers says customer input during development of the app was crucial. More than 100 customers served as beta testers, and above all they called for simplicity. Flowers agreed that users should be able to find information in as few clicks as possible. "Multiple screens for one answer is cumbersome," he says.Launched in January, shortly after the airport began offering free Wi-Fi, the DFW mobile app helps travelers find available parking spots when arriving at the airport, locate shops and restaurants within a five-minute walk from their gate, and get real-time notifications about gate changes.The alerts about gate changes are especially important to the 60 percent of DFW travelers who are trying to catch a connecting flight, says Flowers. "You can have 250 gate changes in a four-hour time frame."The app--available for iOS, BlackBerry and Android devices--has been downloaded over 6,000 times since its launch, Flowers says.With all the information the airport needs to communicate on a daily basis, a mobile app can be a huge cost-saver, says Jack Gold, principal analyst and founder of J. Gold Associates. "Airports have been dealing with the cost of operations that are through the roof," he says. "If you can eliminate the need to employ people, and people waiting in lines, it can have pretty significant ROI."Flowers says DFW's app also has a feedback section that lets users submit comments, take surveys or report concerns about the app or the airport in general. The ultimate goal, he says, is to give travelers a trouble-free airport experience.Lauren Brousell is a staff writer for CIO magazine. Follow everything from CIO.com on Twitter @CIOonline, Facebook, Google + and LinkedIn.