The NHS Covid-19 App is now compatible with contact-tracing apps across Scotland, Northern Ireland, Jersey and Gibraltar.

From 5 November, the NHS Covid-19 App will send an alert if it detects someone has been in ‘close contact’ with a person who has tested positive for coronavirus and is using the Protect Scotland, StopCovid NI, Jersey COVID alert or Beat COVID Gibraltar apps.

In a blog post, the Department of Health and Social Care said the ability for the app to work across the UK borders was a “clear priority” since the technology was launched on 24 September.

This follows an announcement from the Scottish government has announced last month that it had interlinked its Protect Scotland app with Northern Ireland’s StopCovid NI app or Jersey’s Covid Alert app.

Since it was launched, the NHS Covid-19 app has been downloaded more than 19 million times. It was updated recently to improve accuracy and notifications which was “expected to increase the number of people asked to self-isolate by the app”.

Based on APIs from Apple and Google, the app uses Bluetooth technology to track time and distance between smartphone devices.

It also offers a QR code check-in capability at bars, restaurants, and other venues, designed to aid NHS Test and Trace in contacting customers with public health advice should there be a Covid-19 outbreak.

If a user comes into close contact with someone who later tests positive for the virus and needs to self-isolate, the app will send a message stating it has “detected that you have been in contact with someone who has coronavirus. Please stay at home and self-isolate to keep yourself and others safe”.