The NHS Covid-19 app has been launched in England and Wales following months of setbacks. The NHS has been working on the app, which forms an integral part of the Test and Trace programme, since March. Senior reporter, Andrea Downey, looks back at what has happened since then.

It has been seven months since it was first reported NHSX was developing a contact-tracing app which aimed to monitor and contain the spread of Covid-19.

After an initial trial in May the app was abandoned due to technical failings, with the government announcing it would work with Apple and Google using the tech giants APIs to develop a new version of the app.

A trial of that version was announced on 13 August, again involving the Isle of Wight as well as NHS volunteer respondents in the UK. From the following week residents in the London borough of Newham will start trialing the app.

The revamped app, based on Apple and Google’s technology, was launched across England and Wales on 24 September.

The total cost of the app is expected to top £35 million. Some £25 million is expected to be spent this financial year on the new app, while a further £10 million was spent developing the original operating model that was abandoned following heavy criticism relating to data protection and privacy.

Big app-spirations

It was first reported that NHSX was working on a contact-tracing app as part of a digital solution to managing the pandemic in late March.

Based on Bluetooth technology, the app was designed to track time and distance between devices in order to determine which contacts were most at risk if another app user was diagnosed.

The app relied on the self-reporting of symptoms, which would later cause concern with privacy experts as well as the government’s own ethics advisory board – but more on that later.

Once a user had input their symptoms and was deemed to be a likely case of coronavirus their contacts would then be notified with appropriate advice to self-isolate.

Google it?

Shortly after NHSX revealed they were working on a contact-tracing app, tech giants Apple and Google announced they were joining forces in the fight against Covid-19.

In early April, the companies said they would create contact-tracing technology to enable the use of Bluetooth to help governments and health authorities track the spread of the virus.

The solution would be interoperable with both iOS and Android devices using apps from public health bodies, allowing health services to view data from every person who has opted-in to trace Covid-19.

But the key difference was Apple and Google’s technology was based on a decentralised approach, meaning data was only ever to be shared between devices.

Whereas NHSX’s app was based on a centralised model, which would see data collected by the app sent to a central NHS database.

Gould told parliament’s science and technology committee that a centralised approach offered “profound benefits” for tracking the virus and suggested waiting for Apple and Google to release their APIs would slow development down.

However, Apple and Google released their APIs on 21 May, before we had a concrete date for the roll-out of the NHSX app.

Risky business

From the offset, contact-tracing apps globally faced criticism and concern from privacy experts and campaigners.

A majority of concerns were related to NHSX’s decision to go down the centralised route, with many experts suggesting this offered less security and data protection.

An open letter, published on 19 April and signed by hundreds of professors from 26 countries, warned contact-tracing apps could “catastrophically hamper trust” if they become a tool for “large scale data collection on the population”.

They urged governments and public health authorities to evaluate the potential dangers of developing contact-tracing technology before releasing an app to market.

At the same time the Ada Lovelace Institute published a rapid review of the technical, social and public health evidence for contact-tracing apps, finding the current “technical limitations” and “social impacts” outweigh the potential benefits of an app.

From there the debate ramped up. BCS, The Chartered Institute for IT, warned those making contact-tracing apps need to have the right privacy measures in place if they are to convince the public to use them.

In late May, Polly Sanderson, policy counsel at think tank Future of Privacy Forum, told Digital Health News there were “serious issues” with the app relying on the self-reporting of symptoms instead of verified diagnoses, including data poisoning.

She said the basis for a centralised approach to contact-tracing was based on the “shaky assumption” that self-reporting of symptoms is epidemiologically better.

Professor Christophe Fraser, of Oxford’s Big Data Institute which was advising NHSX on the app, defended the decision to rely on self-reporting, telling parliaments science and technology committee that waiting for test results would result in “less control” of the virus, risking a resurgence.

Trouble at home

Concerns about the app’s security and reliance on self-reporting were not exclusively from independent experts.

The government’s own ethics advisory board, set up in April to oversee the development of the app, wrote to health secretary Matt Hancock warning unreliable contact-tracing apps could provide a false sense of security and increase the spread of Covid-19.

Chair Jonathon Montgomery raised concerns about the risk of false positives from an app relying solely on self-reporting of symptoms.

Dr Ian Levy, the technical director of the National Cyber Security Centre, also acknowledged privacy risks associated with the app exist “in theory” but that it would require more data to be considered a threat.

Meanwhile, parliaments joint committee on human rights had called for the government to enshrine in law the parameters in which data collected by the app would be used.

Testing times

Despite the concerns, NHSX launched a trial of the app on the Isle of Wight in the first week of May.

Both health secretary Matt Hancock and NHSX chief Matthew Gould had said they expected the app to be rolled-out nationally by mid-May.

But when the NHS Test and Trace System was launched on 28 May the app was notably missing.

By now it had been downgraded from being integral to the tracing service to being the “cherry on the cake”. Questions began to be asked on whether the UK would actually see a contact-tracing app before lockdown measures were eased.

Prior to the launch of the Test and Trace System, Prime Minister Boris Johnson had told parliament the UK would have a “world-beating” tracing system in place by June, further fueling questions on why the app was delayed.

After weeks of silence, the government finally announced on 18 June it was abandoning its contact-tracing app and would instead be working with Apple and Google to develop a new version – something experts had been urging for months.

The government had been running field tests on both versions of the technology, which found the NHSX version was able to register about 75% of nearby Android devices, but just 4% of iPhones.

The Apple and Google model was more accurate, logging 99% of Android devices and iPhones, but had difficulty measuring the distance between users’ devices.

Baroness Dido Harding, chair of the Test and Trace service said neither version was fit for purpose and that NHSX would focus on creating an app that would “enable anyone with a smartphone to engage with every aspect of the NHS test and trace service”.

More silence ensued on the progress of the app until a second trial of the revamped version was announced on 13 August and later launched on 24 September.

It was downloaded more than 10 million times in the first three days.

The revamped app has a number of features alongside symptom checking and alerts.

This includes:

  • QR check-in, which will alert users if they have recently visited a venue where they may have been exposed to the virus
  • The ability to book a free test
  • An isolation countdown timer to remind people how long they must quarantine for

The app is designed to compliment the Test and Trace programme but won’t share personal data with the system, as per Apple and Google’s decentralised system.

Following the launch many users were unable to add their tests results to the app if they had requested a test elsewhere. Test results taken as a result of Office for National Statistics surveys, and those processed by an NHS hospital or Public Health England lab were initially not able to be shared via the app.

The Department of Health and Social Care (DHSC) later confirmed everyone who receives a positive test result can now log their result on the app, but further developments were underway to allow negative test results to be entered.