Romain Lacombe: A personal air-quality tracker that lets you know what you're breathing

How often do you think about the air you're breathing? Probably not enough, says entrepreneur and TED Fellow Romain Lacombe. He introduces Flow: a personal air-quality tracker that fits in your hand and monitors pollution levels in real time. See how this device could help you track and understand pollution street by street, hour by hour — and empower you to take action to improve your health.