The NHS COVID-19 app is no longer in use and the Isle of Wight trial has now ended. This is archived information from 18 June 2020. If you still have the app, please uninstall it.
Once you tell the NHS through the app that you have symptoms of coronavirus, other app users you’ve been near to should get an alert within 4 hours.
The precise details will depend on the number and length of contacts - the app will work based on a risk model that will be approved by the Chief Medical Officer, and which will be published.