Air pollution in China is already 30 percent worse this year than last year—so bad it's broken records. Every year, the bad air kills over a million people prematurely. And the pollution doesn't stop there. Factories and power plants also pollute water and soil where food is grown. The biggest problem is that public info on pollution is hard to find, which is where Danger Maps comes in. Crowdsourced from Chinese citizens, it's a useful map of potentially hazardous places.