It wouldn’t be realistic for people to get tested on a daily basis, but a study from Mount Sinai researchers called the Warrior Watch Study has found that smartwatches, specifically the Apple Watch, can be used to detect and predict a COVID-19 diagnosis a week before the user takes a swab test.
This study took place back between April and September of 2020 and involved several hundred healthcare workers. The study also looked at heart rate variability as one of the signs that a person could be infected. This is because heart rate variability is an indicator of how strained a person’s nervous system is, which could also be an indication that they aren’t feeling well.
While not exactly an indicator of COVID-19 per se, but it might be better for someone to get tested earlier rather than later. Plus being able to detect an infection earlier could also mean that the person could begin treatment sooner.