The Department of Health and Social Care said that as of 27th September, more than 10 million people have downloaded the app, with six million of those on the first day.

The latest version of the app was launched on 24th September, and has been based on a ‘decentralised’ approach using technology designed by Apple and Google.

Features of the app include contract tracing using Bluetooth, risk alerts based on people’s postcode or district, QR check-in at venues, Covid-19 test bookings and symptom checkers.

A previous ‘centralised’ version of the app, which sent data to a central computer server, was abandoned earlier this year following trials on the Isle of Wight.

The government said that Saturday 26th September saw more than 1.5 million check-ins at venues across the country.

More than 460,000 businesses have downloaded and printed QR codes that can be used by the app to check-in users at the premises.

Businesses are expected to display posters about QR codes and record and maintain contact details logs for customers, visitors and staff.

Matt Hancock, the health and social care secretary, said: “The enthusiastic response of more than 10 million people downloading the app in just three days has been absolutely fantastic.

“This is a strong start but we want even more people and businesses getting behind the app because the more of us who download it the more effective it will be.”