Designing mobile apps that will achieve high retention and engagement is a key challenge for developers. Introducing several gamification elements and techniques in the design process can do a great deal to help reach that goal. This session will cover some gamification techniques that can be used in any app. Over the course of this session we will discuss several examples of actual apps and how they used gamification not only in order to boost retention and engagement, but also help with user acquisition. Looking at topics ranging from the evolution of users’ feelings, to social influence, to the unpredictability and variety of rewards, to the manipulation of user behaviour and scarcity, we will aim to provide an overview on how to design apps that engage users with the use of gamification.