Cooperative learning and peer instruction are well documented pedagogies that engage students in their learning process. The means to implement cooperative learning in the classroom have evolved from raised hands, colored flashcards, student response systems or “clickers”, to web-based audience response systems that work on any electronic device. This paper briefly reviews available audience response systems and presents a case study on Learning Catalytics, a system designed to enable peer instruction and implement just-in-time teaching pedagogy.