If you have iPhone you can measure your heart and respiratory rate with app, thanks to
Google to add heart and respiratory rate tracking to Android phones - CNET
Google Fit app gets heart and respiratory rate monitoring feature for Pixel phones
Google Fit measures heart, respiratory rate w/ phone camera - 9to5Google
Google Pixel to Receive Google Fit Features Including Respiratory, Heart Rate Measurements
iPhone users can now measure heart & respiratory rates using Google Fit app
Update: Wider rollout] Pixel 6 gets Early Access heart rate and respiratory tracking in Google Fit
How to Measure Heart Rate and Respiratory Rate Using Your Pixel Phone
Google Fit Now Lets You Measure Your Heart Rate Using Your IPhone's Camera
If you have iPhone you can measure your heart and respiratory rate with app, thanks to Google