The UK is to stop developing its own Coronavirus contact tracing app and switch to building a new one that is constructed around a different philosophy.
NHSX’s original design, which progressed to the point of being built and tested, took – in international terms – a lonely path.
While many other nations began building their apps around technology jointly designed by Google and Apple, the UK built its system from the ground up.
Critically, the UK chose a centralised model where users’ phones would send contact data back to the NHS. This approach could, it was felt, protect people and also help deepen scientific understanding of the Coronavirus and how it spreads across a population.
The BCS Voice
Ahead of the UK Government’s direction change, BCS, The Chartered Institute for IT issued a policy positioning paper drawing on members’ experience. It recommended extensive testing and a strong communications campaign to increase public confidence in the technical and ethical aspects of the app.
Kathy Farndon, Vice President, BCS, The Chartered Institute for IT, said: ‘The biggest threat to the success of the contact-tracing app is that perceived “Big Brother” elements of the implementation, for example, the use of a centralised database, may have a negative effect on uptake from the public and minimise the chance of reaching the 60% uptake implementation target.’
Dr Bill Mitchell OBE, Director of Policy at BCS, The Chartered Institute for IT, said: ‘BCS is clear that if done ethically and competently a tracing app can make a huge contribution to stopping the spread of COVID-19; but a majority of our members don’t believe the current model will work and are worried about the reliance on a centralised database.’
The other path
By comparison, the Google and Apple approach keeps all necessary data on the users’ phones. This decentralised design provides little or no useful information to health authorities but does protect users’ privacy much more fully.
Though elegantly designed and with a sharp focus on anonymity, privacy researchers found the first NHS app could reveal details about users’ locations.
These genuine technical concerns, coupled with historic worries about government led IT and data gathering projects, caused observers, analysts and the public to be deeply sceptical about the app’s chances of success.
Technical limitations
Beyond privacy worries, the UK app faced another hurdle: Bluetooth. To work, most contact tracing apps used Bluetooth as a means of measuring closeness to other users’ phones.
Critically, the UK app used Bluetooth in ways not naturally supported by Apple and Google’s mobile phone operating systems.
A UK technical workaround saw the app being tested in the Isle of White. But, officials admitted that the first UK app only worked on ‘4% of Apple phones and 75% of Google phones.’ Rumours that the UK was developing a second, decentralised app began to circulate on social media and in the press.
France, another country that chose to design and develop a centralised contact tracing app, is facing difficulties. Though reports suggest it has been downloaded a million times, it is proving hard to link with other European countries’ decentralised apps. This means pan-European Coronavirus protection could be hampered.
The French app has been downloaded by around 2% of the nation’s population. This compares with Germany where 6% of its population has downloaded its Corona-War-App – a decentralised application.
Here are the key steps and talking points that led up to the UK Government’s change of heart.
1. Risk and reward
Bill Mitchell, Director of Policy at BCS, says: ‘A lot of debate focuses on the NHS app’s ability to do good… its ability to help prevent the spread of coronavirus versus its potential for compromising users’ privacy. The key consideration is, how much data might the app reveal? What sort of data is it? Is this data of any actual intrinsic value? Is data with a theoretical value worth more than the opportunity to slow the virus’ spread?’
Continuing, Mitchell says: ‘And remember, however much data the NHS app may reveal will be inconsequential relative to the huge amounts of personal data we gladly - and willingly - reveal about ourselves to the internet and social media giants as we consume their services.'
2. Contact tracing apps: the theory
When it comes to fighting COVID-19, experts agree on one point: preventing transmission is a priority. The problem is, the virus is spreading too quickly for manual contact tracing to be effective. A technical solution is needed.
Most contact tracing apps work on a similar theory: they record information about your closeness to other people and for how long you were near to them. As closeness increases and the duration of that closeness rises, so the probability of potential infection will go up.
Such apps try to do this anonymously and by using the very minimum amount of data. Anonymously, in this context, is generally taken to mean: without revealing much, if anything, about the user’s identity and location.
Of the different app models in development and deployment around the world, most then require the user to tell the app when they are feeling poorly. This self-identification then triggers several different responses - both at the level of the app’s interface and in the app’s back end infrastructure. It’s on what happens after self-identification that we’ll focus our efforts.
