The app is designed to motivate UvA students to make sustainable choices about their waste production and overall environmental impact. It works by providing the user with challenges centered around sustainability - for example, packing lunches in reusable containers, rather than purchasing a packaged lunch. Once challenges are completed, users earn sustainability points that can be traded for rewards (discounts from our sustainable partners). Combined points also contribute to users’ place on the leaderboard, allowing users to compete with other students. The gamification-based system utilizes evidence-based intervention strategies for behavioral change, such as nudges, goal setting, and competition.