One of the main symptoms of COVID-19 is low levels of oxygen in a person’s blood, even when they feel fine. So when the pandemic started spreading, doctors would always measure your blood oxygen levels with a pulse oximeter: a special clip attached to your finger or ear.
But soon, you will be able to do it at home with the same accuracy. All you’ll need is the device you use for taking selfies or mindlessly scrolling through Instagram in bed. That’s right – your phone.