Starting next month, the feature will be made available as an update to Google Fit, the company’s health tracking app, on Pixel phones with plans of making it available to more users by expanding support to non-Pixel phones in the future. “Heart rate and respiratory rate are two vital signs commonly used to assess your health and wellness. Starting next month, Google Fit will allow you to measure your heart rate and respiratory rate using just your phone’s camera. These features will be available in the Google Fit app for Pixel phones, with plans to expand to more Android devices,” Shwetak Patel, Director of Health Technologies at Google Health, wrote in a blog post. To measure your respiratory rate, you just need to place your head and upper torso in view of your phone’s front-facing camera and breathe normally. This allows the phone’s camera to monitor the rise and fall of your chest, from which it can calculate the respiratory rate. To capture your heart rate, you need to simply place your finger on the rear-facing camera lens. The app then follows subtle colour changes in the fingertip as blood flows from your heart through your body. “Thanks to increasingly powerful sensors and advances in computer vision, these features let you use your smartphone’s camera to track tiny physical signals at the pixel level — like chest movements to measure your respiratory rate and subtle changes in the colour of your fingers for your heart rate,” added Patel. Google has already completed initial clinical studies to validate both features that were developed in-house. These features work in a variety of real-world conditions and for as many people as possible. The post notes that the “heart rate algorithm relies on approximating blood flow from colour changes in someone’s fingertip” and accounts “for factors such as lighting, skin tone, age and more in order to work for everyone.” According to Patel, the features are only intended to let users track and improve day-to-day wellness. The results are not intended for medical purposes and should not be used to diagnose, treat, cure, or prevent any disease or medical condition. The idea is to help people who rely on the Google Fit app to monitor their daily wellness, alongside other health and wellness information.