DDB Stockholm brings Pong-like fun into its latest interactive outdoor effort for McDonald's, Pick N' Play. Passersby are invited to use their mobile phones as controllers for a digital paddle game on a Stockholm billboard, no app download required. Players choose their treats and if they last for more than 30 seconds, they score a coupon earning them free fast food at a nearby golden arches.,

The effort continues DDB's other innovative outdoor tactics like this one, which challenged pedestrians to take a picture of McDonald's food to get it for free.