The pioneering app must be downloaded by 50-60 per cent of the nation to be effective, Transport Secretary Grant Shapps said yesterday.
People arriving into the UK at airports will be ordered to download the app before they are allowed into the country.
The app will be trialed on the Isle of Wight’s 150,000 population this week before national roll-out in two to three weeks’ time.
The app will help the Government’s new contact tracing system due to be launched in two weeks, which will chase down fresh outbreaks of coronavirus and alert people who they came in contact with so they can self-isolate.
Mr Shapps said it was the duty of every Brit who has a smart phone to download the app to stop people dying from coronavirus.
Mr Shapps said the high turnout of Brits clapping NHS workers every Thursday evening showed people wanted to support the NHS and he said they will now have another means to show that support.
Mr Shapps said: “The idea is that we will encourage as many people to take this up as possible, this is going to be a huge national effort.
“We need for this to work, 50, 60 per cent of people to be using this app.”