The app is more than just a nice amenity. Westin's parent company, Starwood Hotels & Resorts Worldwide (No. 400 on the Fortune 500), believes such technological innovation is at the heart of a larger strategy to drive guest loyalty. Like points programs that reward frequent visitors with free or discounted rooms, the company hopes personalized apps and other cool tools will help retain customers. (A handful of Starwood's Aloft locations let guests bypass registration by using their smartphones to check in; special reusable keycards can be remotely preprogrammed to unlock a guest's room.) "What technology can do is take the intimacy of that one-to-one relationship you might have with a favorite hotel and make that possible across a system of 1,162 hotels in nearly 100 countries," says CEO Frits van Paasschen.
Many Fortune 500 service and industrial companies, Starwood(HOT, Fortune 500) included, traditionally have thought of themselves as purchasers of hardware and software -- not purveyors of technology. But the proliferation of smartphones and consumers' desire for new ways (think Twitter and Facebook) to interact with companies and brands have forced almost every large corporation to think like a tech company.
Starwood has formed a new team that brings together executives from different areas of the business to develop and build prototypes for tech projects. Developers receive a stream of input from headquarters and managers in the field, and tweak and update the prototypes accordingly.
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Starwood isn't the only hotel operator to launch apps, of course. The trick is to find ways to automatically update and populate apps with customers' preferences -- data that the hotelier probably has stored on a separate software platform -- so guests get exactly the kind of amenities and experiences they like. "The real art and science of this is marrying high tech with human touch," van Paasschen says.
Van Paasschen, who likes to immerse himself in trends (earlier this year he temporarily relocated headquarters to Dubai, partly to get a better sense of the region), has found a way to understand how his customers use technology: Last year he gave up his laptop and desktop and now works only on a tablet.
This story is from the October 07, 2013 issue of Fortune.