With around 2 million daily active users, RockYou's Super Wall is one of the most popular applications on Facebook. And RockYou.com, which provides slideshow creation tools to young consumers, attracts 20 million unique visitors per month. To better understand the thinking and design approaches that brought on success for this small startup, Forrester spoke with Jia Shen, CTO and co-founder. Our discussion uncovered five key design suggestions for engaging young consumers, such as "target girls first, boys second" and "design for viral messaging and social incentives." Firms looking to fully engage Gen Y should translate and apply RockYou's approach to their own efforts.