Citizen science, aiming at integrating citizens, their commitment and knowledge into scientific research, is a powerful way to create additional research outputs and scientific knowledge. This is particularly true when geospatial technology is used to enable citizens to contribute spatial data. While fields such as biology and ecology make abundant use of geo citizen science, only a limited number of projects approach topics related to geomorphology. Due to climate change and its impact on the Earth’s surface, research activities that use citizen science are considered very useful to support the work of geomorphologists. However, geomorphology is a complex topic to engage with citizens. Thus, to reach and involve citizens in geomorphological research, we need spatial data collection tools that are tailored to their needs and raise their interest in geomorphology. For this, participatory design is a valuable option since it allows us to get comprehensive information about citizens and their requirements and to integrate this information into the development process. Now, does participatory design reveal requirements otherwise unknown to the developers? What additional efforts must be made when cooperating with citizens in participatory design? The citizenMorph project, which addresses these questions, found that detailed and valuable insights can be gained (regarding, e.g., information delivery, design issues, and community building), but also that additional efforts are required in terms of the composition of the project team, the interaction and communication during the development process, and the selection of methods, tools and material to be used.