A Corona app for tracking infection chains was launched in England and Wales with a long delay. The app of the national health service NHS has been available for download in the popular app stores since Thursday. A previous version of the app was tested on the Isle of Wight and in a London district in the summer — but this was stopped again due to technical problems. Similar apps have been in use for months in a number of European countries. Scotland and Northern Ireland also already have their own systems. Like the German Corona warning app, the English app exchanges Bluetooth signals with other cell phones in order to trace contacts anonymously. In addition, the English program also provides information on how high the corona risk is in your own postcode area. It is also intended to specifically warn visitors to restaurants, cinemas or other public spaces if they have previously scanned a QR code in the location.