This App is part of the indoorCO2map.com project , a citizen data collection initiative to collect data about the CO2 concentration in non-residential Buildings (shops, restaurants, hospital etc.). Using this app and a supported CO2 Sensor, you can help creating a large and comprehensive dataset about Indoor CO2-Levels. Currently Aranet4, Airvalent and the Inkbird-IAMT1 Sensors are supported. Support for other sensors will be added later on.