<p>Globally, cities and their infrastructures, people, and ecology systems are experiencing unprecedented changes due to environmental change and anthropogenic pressures. To create the most sustainable approaches for mitigating and adapting to environmental changes, urban designs require a radical rethink that accounts for the needs of local citizens and stakeholders. Decision support systems (DSS) can be utilized to engage with members of the public to elicit their opinions on proposed designs. To better engage citizens, DSSs have started to include the use of virtual reality and augmented reality to demonstrate designs, however, these systems are often only applied to smaller stakeholder engagement events. Here, we created a theory-informed augmented reality application for collaborative crowdsourcing of urban designs. The designed system allows users to manipulate a two-dimensional map with targets representing different objects (e. g., trees, lakes, infrastructure). The changes made to the 2D map are then visualized through a mobile application that displays a 3D AR visualization of the changes the user makes in real time. The resulting application can be used to engage a diversity of participants in a range of urban and environmental planning contexts.</p>