Throughout modernity, science has been synonymous with truth. But replication crises across disciplines and ‘fake news’ have deeply eroded society’s trust in science. The Citizen Science movement is a way to rebuild trust through citizen involvement. The idea is that anyone can contribute to reliable scientific knowledge, and science and science policy are responsive to society’s concerns and needs when they are open and accessible to all. In our recent Wellcome funded project, the Emotional Brain Study, Professor Sarah-Jayne Blakemore and I are collaborating with citizen scientists the world over. The study is conducted using the Emotional Brain Study app, which is free to anyone on Google Play and Apple store. The app is designed to study the development of emotion regulation across the lifespan.