Air Quality Data

Helpful app for Beijing air quality. The on line update is important for Beijing (or other places citizens) to know if a mask is needed. It will be great if this apps was able to provide such information for all cities in the world. China is not the only place with such polluted air. Did someone get something similar for drinkable water?
Regards,

Chris in Beijing.

Bigtotof about Air Matters, v4.0.2