Find or conceive of other applications in which the Internet and mobile devices create direct marketing opportunities. The Internet opened the door for explosive growth in direct marketing, and much of that growth is through applications for mobile devices. For example, for $12.99 per month, Schlage, a lock manufacturer, now offers a wireless, keyless door lock system integrated with cell phones. And Zipcar, a car-sharing service, launched an app for the iPhone enabling customers to not only reserve and locate a car but also unlock it and drive it away—all without contacting a customer service representative. Honking the virtual horn on an iPhone triggers the horn on the reserved car so the member can locate it in the Zipcar lot. The app even looks like a key fob, prompting the user to push the button to unlock the door. Once in the car, swiping a membership card allows access to the keys in the car.