Current citizen science seems effortless...just download an app and start using it. However, there are many technical aspects that are necessary to make a citizen science project work. In this session, we will provide an overview of all the technical elements that are required - from the process of designing an app., to designing and managing a back-end system, to testing the system end to end before deployment. Participants will have the opportunity to engage in a short exercise to consider the design of an app for a citizen science project that addresses light pollution.