From next month, Google Fit users will be able measure heart and respiratory rates without a wearable, by using the phone’s camera. This will be available in the Google Fit app on Pixel phones, with plans to expand to more Android devices.

“Mobile devices have become essential daily tools for people all over the world from staying connected to taking pictures and accessing information,” said Shwetak Patel, director of health technologies at Google Health. “Thanks to sensors that are already built into smartphones – like your microphone, camera and accelerometer – these devices can also be helpful for daily health and wellness.”

Heart rate and respiratory rate are two vital signs commonly used to assess health and wellness.

To measure respiratory rate, users need to place their head and upper torso in view of the phone’s front-facing camera and breathe normally. To measure heart rate, they simply place their finger on the rear-facing camera lens.

“While these measurements aren’t meant for medical diagnosis or to evaluate medical conditions, we hope they can be useful for people using the Google Fit app to track and improve day-to-day wellness,” said Patel.

Once the measurements are made, users can choose to save them in the app to monitor trends over time, alongside other health and wellness information.

Thanks to increasingly powerful sensors and advances in computer vision, these features let the smartphone’s camera track tiny physical signals at the pixel level, such as chest movements to measure respiratory rate and subtle changes in the colour of fingers for heart rate.

“We developed both features and completed initial clinical studies to validate them so they work in a variety of real-world conditions and for as many people as possible,” said Patel.

For example, since the heart rate algorithm relies on approximating blood flow from colour changes in someone’s fingertip, it has to account for factors such as lighting, skin tone, age and more to work for everyone.

“With continued advances in hardware and software, sometimes the device that could be most helpful to your health and wellness is already in your pocket,” said Patel. “Our team of researchers, engineers and clinicians are exploring how everyday devices and inexpensive sensors can give people the information and insights they need to take control of their health.”