The telemetry network consists of fixed and mobile measuring stations throughout Luxembourg located in rural, urban or peri-urban areas. The network measures air quality in real time and monitors the levels of key pollutants, including nitrogen dioxide, ozone and fine particulate matter. This network serves as a basis for informing and alerting the population, especially the sensitive people in case of pollution peaks. It is also in the context of improving public information that an app on air quality has been developed.