The NHS is planning to release a COVID-19 app that will help as part of the Government's test, track and trace strategy that's going to play a part in easing the UK out of lockdown.

The app is currently being tested on the Isle of Wight, before wider release, expected around the middle of May. Debate has raged about whether the app will work exactly as the NHS wants it to, because of restrictions inherent in Google's Android and Apple's iPhone operating systems.

To deal with those sorts of restrictions - which limit access to Bluetooth in the background when an app isn't being used - Apple and Google developed their own API - application programme interface - a tool that enables app developers to access those services more efficiently. 

In its current form, the NHS COVID-19 doesn't use those tools, instead using a different system, to get around the restrictions. The problem is that this isn't a tried and tested method and some other regions, like Australia, have found the app won't communicate when it's not on the screen - a problem that the UK could potentially face. 

The Financial Times, however, is reporting that NHSX - the digital arm of the NHS responsible for developing the app - has changed tack on this problem slightly and has approached a Swiss development firm, Zuhlke Engineering, to investigate the integration of the Apple-Google solution. 

The information, which reportedly comes from contract documents, states that the timeframe for this work is two weeks - which would more or less be in line with the planned launch date for the NHS COVID-19 app rollout.

That might signal an about turn, although this was always a possibility. The UK Government confirmed it was developing a contact tracing app before Apple and Google announced their API. At that point, the Government said that they would look at what that offered and see how it might play a part in the process, so this change of direction shouldn't come as a huge surprise to anyone following the story. 

There's an interesting twist, however, as reported by The Sun. According the tabloid newspaper, the current version of the NHSX app doesn't suffer the problems that the Australian app does, because it's found a workaround for the Apple Bluetooth API.  

"This is the first time that API has been used in this way and using like this is unproven and may cause battery issues," reports The Sun, talking to a source at Apple. That might mean that the app currently being tested in the Isle of Wight will work, but not as efficiently as one using the Apple-Google API. 

Why does all this matter? There's a fundamental difference in approach proposed by NHSX and the US tech giants Apple and Google. The NHS solution wants to be able to gather the data into a centralised database, allowing the UK authorities to get information on localised outbreaks. By having additional data to analyse, the NHS could then potentially be able to spot problem areas and address them. Additionally, the NHS app is designed to be a route to testing, allowing someone who has in contact with a confirmed case of the virus to get a test delivered to them.

Apple and Google have a different approach that keeps the data private, only alerting those who have been into contact with someone developing symptoms of the virus via their phones - and not allowing the NHS access to that information. It would essentially mean that the NHS didn't get access to all the data. While that might better protect the privacy of individuals, it potentially lessens the national response the authorities can take. 

The testing phase that the NHSX app is currently in is exactly that - a testing phase. We wouldn't be surprised if changes were to come down the line in the next couple of weeks - but given that there is a technical and ethical argument around the app, we doubt that all sides will ever be completely satisfied with the outcome.