NHS coronavirus tracing app plagued with technical difficulties within hours of launching

As the software is voluntary, its success will also depend heavily on how many people choose to download and use it.

An advertising campaign to promote the app will appear on television on Thursday evening with the strapline, “Protect your loved ones. Get the app”.

Mr Hancock added the “vast majority” of people had the right software, adding that some may need to upgrade their phone’s operating system.

The new app requires Apple users to be running iOS 13.5, which was rolled out in May and works on the iPhone 6s, released in 2015, or newer handsets, while Android users need to be running at least Android version 6.0, which was also first released in 2015.

The Government said that anyone unable to use the app should continue to use traditional contact tracing services provided by NHS Test and Trace or, NHS Wales Test, Trace, Protect.

The app is powered by an Apple and Google-developed system, using Bluetooth to keep an anonymous log of people a user has been close to.

It does this by exchanging randomised keys while the Bluetooth signal strength measures proximity.

If someone falls ill, they can tell the app, which will then ping their keys to a central server and in turn send them off to all app users in search of a match.

Should the system determine a person as a close contact, they will be automatically be sent a notification and issued with further guidance.

A QR code scanning feature is available, allowing people to check in to venues they visit and easily share their contact details for human tracing efforts.

Some 160,000 businesses have already downloaded QR codes for use in their facilities.

The Department for Health and Social Care has been contacted for comment.