AirVoice

In AirVoice app you'll find you'll find minute-by-minute updates on air quality from a network of professional monitoring stations. 
Use it to make important health decisions every day - whether to open windows, play outdoor sports or take your child for a walk.The AirVoice app enables its users to do the following:
• select a city on the world map;
• use calendar for viewing historical data on city air quality;
• view general air quality index for the city and station indexes in selected areas;
• track the parameters that make up the air quality index: PM2.5, PM10, CO, NO2, O3, SO2, H2S.
• view information on fires around the world to better understand the causes of air quality deterioration.
— How is the Air Quality Index (AQI) calculated?
The AQI (Air Quality Index) is based on the highest concentration of the most hazardous measured substance in the past 24 hours.
— What does a city's general index consist of?
The general index is calculated based on the readings of the monitoring station that recorded the highest concentrations of pollutants. To get an accurate estimate of the air quality in your location, use the monitoring station closest to you.
— How reliable are the monitoring stations that measure substance concentrations for the AirVoice application?
CityAir compact monitoring stations are comparable in accuracy to the reference equipment used in government monitoring networks.