Városszervíz (City Service) is a mobile application where residents can report appropriate urban management errors and problems and the correction process can be followed. The application works in the field connected to the system operators. With City Service the citizens can be esaily involved in city maintenance tasks with a smart phone application. The starting point of the concept is that people like to help and participate in the maintenance work if you make it them simple, interesting and experience-like. The service is based on a downloadable application with which you can notify the city with photos and GPS coordinates about the problems you have experienced. For example such cases can be reported: street lighting faults, damaged street objects (benches, railings, public sculptures) full waste bins, bumps. Photos taken with your mobile device with GPS coordinates of the location will appear immediately at service provider so the repairs are faster and more accurate and efficient. On the web interface the citizens, service providers and the city administration can monitor the reported errors and their corrections. Thus in the system the dangerous situations can have faster response and the applicants will be more motivated if they have positive feedback. Overall the image and sustainability of the city is greatly improved and this service has a good light on the municipality work too.