Pulse oximeters and other devices to monitor aspects of our health may work better for some than for others.
In recent years, there’s been a veritable explosion in the number and type of health monitoring devices available in smartphones and fitness apps.
Your smartphone is likely tracking the number of steps you take, how far and fast you walk, and how many flights of stairs you climb each day. Some phones log sleep, heart rate, how much energy you’re burning, and…
