Every person who downloads the NHS coronavirus contact tracing app will be helping “make the country a safer place”, the health secretary has told Sky News.
Speaking to Kay Burley, Matt Hancock said the app – which has finally been launched in England and Wales after months of delay and questions about its effectiveness – was a “helpful tool” in the fight against COVID-19.
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Asked what percentage of the population would need to download it for it to be effective, Mr Hancock said “there isn’t a figure for that”.
“Every single person who downloads the app is helping to improve how it can keep us safe. It helps you to keep yourself and your loved ones safe,” the health secretary said.
“Every additional person downloading it will make the country a safer place.”
He added: “Even if only two people downloaded it and they came into close contact and one had tested positive, then it would work for the other.
“Of course it’s true that the more people download it the more effective it will be, but this is just one part of our overall plan for tackling coronavirus.”
Scotland and Northern Ireland have already launched their own contact tracing apps.
The NHS app for England and Wales – which is available to download on iPhone and Android – was trialled first on the Isle of Wight and in the London borough of Newham, and was used to send alerts to users after someone had tested positive.
It uses 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 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.
However, as the software is voluntary, its success will depend heavily on how many people choose to download and use it.
The government had originally tried to develop its own app software before deciding in June that it needed to co-operate with companies which provide the technology powering smartphones to come up with an effective product.
A TV advertising campaign with the slogan “Protect your loved ones. Get the app” is being used to encourage people to install the software.
The UK’s major network operators, including Vodafone, Three, EE and O2, giffgaff, Tesco Mobile, Sky Mobile and Virgin Mobile have all agreed to not charge for using it.
Baroness Dido Harding, executive chair of England’s NHS Test and Trace Programme, said: “We want to make it as easy as possible for everyone to engage with England’s NHS Test and Trace service.
“The NHS COVID-19 app enables the majority of people with a smartphone to find out if they are at risk of having caught the virus and need to self isolate, order a test if they have symptoms, and access the right guidance and advice.
“The features of this app, including QR code check-in at venues, work alongside our traditional contact tracing service and will help us to reach more people quickly in their communities to prevent further spread of the virus.
“This is a welcome step in protecting those around us.”