Barclaycard's WaterSlide Cost: Free U.K. credit card company Barclaycard's WaterSlide app, a game that lets players ride a virtual waterslide, has scored more than 12 million downloads since its mid-2009 launch, making it one of the most successful branded apps of all time. The app follows a popular Barclaycard commercial that featured an office worker tearing off his clothes and riding through the city on a waterslide while using his card to pay for things like groceries. Gamers steer their way down the waterslide by tilting or rotating their iPhones, controlling their speed as they go. They win points by collecting virtual items and avoiding obstacles like evil ducks and crabs that will slow them down through nine different levels. Players can choose to navigate through the urban waterslide as a male or female character and decide if they want a camera view through first or third person. We were impressed with the game's quality and especially liked how you could see virtual water bubbles appear on the screen, but found the levels somewhat repetitive.