eRouška is a mobile application that is used by the Czech people to notify other people that they may have been exposed to the COVID-19 virus. The application works by detecting a low energy Bluetooth signal, which is emitted by infected users. It can also be used to notify individuals that they may have been in contact with the infected individual, even if the individual didn't have the app installed.

The eRouška application is a useful tool for the people of the Czech Republic and is intended to help the country fight against the COVID-19 pandemic. The eRouška application is able to determine that contact has taken place between two users, even if the individuals don't have the app installed.