Air Quality is among the most environmental issues impacting the urban populations. Traditional air quality networks can assess time trends and assess compliance to air quality regulations, but to understand sources and assess exposure. The RI-URBANS project is a European initiative aiming to develop new strategies and enhance the existing tools to address the air quality challenges and societal needs in European cities. This paper presents an overview of the pilots of the RI-URBANS project associated with air quality mapping and pollution hotspot identification using modelling, novel measuring methodologies and mapping techniques. Special focus is given on the discussion of the novel measuring methodologies introduced with the use of low-cost sensors, mobile measurements and citizen participation in the data collection process, with pilot projects undertaken in the core pilot cities in Europe and other projects from cities outside the pilot's core. The findings highlight the significance of participatory science, technological advancements in air quality measurement, and the potential for policy integration. The project's outcomes suggest that integrating stationary sensor networks, mobile monitoring platforms, and citizen engagement can significantly enhance urban air quality management, alongside traditional monitoring and modelling methodologies. This study highlights the important work undertaken by the participating cities and the novel approaches to disentangle the complicated air pollution patterns and improve the air quality for everyone, while making this crucial information easily obtainable.