Plume Air Report is a weather forecasting app for urban air pollution.  The free app, developed by Plume Labs, tells you if it’s safe to run, bike, go out with your children or eat outside.

To do this, the company relies on thousands of pollution monitoring stations. The company aggregates the usual suspects, nitrogen dioxide (NO2), ozone (O3) and particulate matter (PM2.5 and PM10), and then hides all the complexity behind a simple index.  The app covers over 150 cities around the world.  Check it out!