Google feature to allow measuring heart rate, respiratory rate through phones

Two vital signs commonly used to assess health and wellness — heart rate and respiratory rate — can now be measured using a cell phone, Google has said, announcing that starting next month, these features will be available in the Google Fit app for Pixel phones.

It uses a smartphone camera and a computer vision technique called optical flow to detect respiratory rate via subtle movements in the chest for measuring respiratory rate.

For the heart rate, it uses a smartphone camera to detect subtle colour changes in the fingertip that happen when freshly oxygenated blood flows from your heart through your body.