Stay far far away guys - doctor here, this makes zero sense medically. If they are using the app to monitor asthma the diagnosis has already been established and then it is a matter of machine learning to manage a chronic condition. This base already has issues and will likely need years of work and tweaking machine learning to show any benefit.

You cannot extrapolate this to diagnosing Covid. Any patient with a cough can have Covid. They can also have any number of other things. As mentioned you can also have asymptomatic Covid or Covid with all the other symptoms except cough. Ignore or watch from a distance as it gets hyped up and then collapses.