The national contact tracing service has started today (28 May), guidance and info is available here:
The app is free and simple to use. Once you’ve downloaded the app, Bluetooth technology on your phone will record the distance between other phones that also have the app installed. If you become unwell with symptoms of coronavirus, you can allow the app to inform the NHS. This will trigger a notification that the NHS will then send anonymously to all other app users who you’ve been in significant contact with over the previous few days. Affected app users will be sent official NHS advice on what to do next.
If you are concerned about whether a call, text or email is genuine, you can check the NHS England Test and Trace service website or the Scottish Government Test and Protect website or the Public Health Agency website in Northern Ireland.
Genuine contract tracers will never ask you for any financial information such as credit card or bank details.
They will also not ask you to set up a password or Pin over the phone, or to call a premium rate number, such as those starting 09 or 087.
If you don’t want to talk over the phone in England, you can ask for an email or text inviting you to log into the web-based service instead.https://covid19.nhs.uk/