The Corona-Warn-App is an offer of the German government and helps to break through infection chains quickly.
But how does it work?
If you meet another user, encrypted random codes are automatically exchanged between the smartphones. The duration and the distance during the encounter are stored. It reveals neither names nor locations, so privacy is protected. If a user has been proven to be infected, he can anonymously make his own random codes available to all other users. The app finds the code that your mobile phone exchanged with the smartphone of the infected person at the time and informs you that you had contact with him or her.
“The more people who use the app, the greater the benefits,” says the Chancellor. In this way, the Corona -Warn- App protects us and others.
You can find out exactly how it works and what it can do at: https://www.bundesregierung.de/breg-de/themen/corona-warn-app/corona-warn-app-englisch