Google Fit App will now allow Pixel users to measure heart and respiration rate using smartphone camera

Pixel smartphones will use camera sensors to detect someone's chest moving as they breathe, calculating their respiration rate.

from http://www.firstpost.com/tech/news-analysis/google-fit-app-will-now-allow-pixel-users-to-measure-heart-and-respiration-rate-using-smartphone-camera-9274091.html