The app requires an internet connection at regular intervals throughout the day. This is to download a list of anonymous IDs of people who have recently tested positive for coronavirus.

The amount of data used will vary from day to day, depending on how many coronavirus cases there are. The app team will be carefully monitoring data usage to make sure it remains at a reasonable level.

Major phone operators in England and Wales, including Vodafone, Three, EE, O2 (including giffgaff and Tesco mobile), Sky, and Virgin, are supporting NHS COVID-19 app users by ‘zero-rating’ data charges for all in-app activity. This means customers will not be charged for data when using the in-app functions, or if they are directed out of the app to websites.

Don’t worry if your internet connection is unreliable. Alerts and notifications from the app will be queued and sent to you as soon as you’re back online.