As far as I understood the apps are designed to measure time of being near someone as well. I think within X meters for Y minutes (based on how often the bluet

As far as I understood the apps are designed to measure time of being near someone as well. I think within X meters for Y minutes (based on how often the bluetooth pings are exchanged). This also has basis in virology where rate of infection for flu/corona substantially increases when you are close to someone within X meters (say 1.5m) for longer than a defined time Y (say 10min).