uCrowds provides a crowd simulation solution which allows real time changes with superior performance. uCrowds is a spin-off from academic research from Utrecht University and maintains tight connections to academia, bringing the latest research directly into practice. We offer a user-friendly desktop application, SimCrowds, which enables crowd managers, event organizers, and consultants to create and simulate interactive crowds. The simulation handles 100 000+ pedestrians in real-time in 2D and multi-layered 3D environments on a consumer PC. Users have created simulations for e.g. the Tour de France, Vuelta and Schiphol airport. Next, we help with projects were we integrate our engine into other software environments. * uCrowds' versatile crowd simulation engine has powered digital twins of large environments, such as the city of London and Las Vegas, featuring cloud-based solutions with 1 000 000+ real-time pedestrians. * We have added interactive crowd simulations in a multi-layered, synthetic airport, allowing architects to optimize performance, improve user experience and reduce costs under on various occupation situations. * Our software is applied in museums to interactively play with simulations and learn about its importance.