The UK government is reportedly preparing to launch an app that will warn users if they are in close proximity to someone who has tested positive for coronavirus.

The contact-tracking app will be released just before the lockdown is lifted or in its immediate aftermath, Sky News has reported and will use short-range Bluetooth signals to detect other phones in close vicinity and then store a record of those contacts on the device.

If somebody tests positive for COVID-19, they will be able to upload those contacts, who can then be alerted – via the app.

This means that the data will not be regularly shared with a central authority, potentially easing concerns around privacy violations.

If people with the app later test positive for coronavirus, they could allow all the folks they’ve been near to be informed, so those people could self-isolate.

Jim Killock, executive director of the Open Rights Group, told IT Pro that the new app, and similar developments, might “prove to be important tools in the fight against COVID-19”. However, he also raised concerns about the privacy of users.

“Nevertheless, we are concerned that [the] government needs to put more effort into helping people understand their approach to privacy more generally, and improve their communications vastly. Building a project like this at speed carries privacy, security and delivery risks, so the more information that is given out the better,” he said.

NHSX, the innovation arm of the UK’s National Health Service, will reportedly appoint an ethics board to oversee the development of the app, with its board members set to be announced over the coming weeks.

“It is good that they are thinking about the privacy of users – this is essential to build trust and confidence so people use it,” said Killock.

Questions might arise over the effectiveness of the app, as large numbers of people will be required to use it in order for it to work efficiently. The NHS is reportedly counting on the app being downloaded by more than 50% of the population.

“NHSX is looking at whether app-based solutions might be helpful in tracking and managing coronavirus, and we have assembled expertise from inside and outside the organization to do this as rapidly as possible,” an NHSX spokesperson said.

Only last week, the NHSX and Matt Hancock MP were urged to follow steps that would guarantee that new technologies used to tackle the coronavirus outbreak abide by data protection ethics.

In an open letter signed by numerous “responsible technologists”, they were asked to take urgent steps to ensure that the public’s trust in the NHS is not undermined by possible data breaches.