‘Loading’ bug in NHS Covid-19 contact tracing app fixed by Google

The bug reportedly created delays in the app’s ability to conduct regular exposure checks and caused a “loading” notification to appear that could not be removed.

Google said it had found and fixed a fault within its Exposure Notification System which is the underlying framework that allows devices to communicate with each other.

The app, which is used in England and Wales to improve their Test and Trace system, uses Bluetooth on smartphones to keep an anonymous log of other app users that an individual comes into contact with, informing them if they have been near someone who tests positive for the virus and what to do next.

“Late in the evening on January 12, an issue with the Exposure Notifications System on Android began causing delays in the checking of potential exposures for those with apps installed,” a Google spokesperson said in a statement on the incident.

“We have issued a fix. It may take a few hours for devices to catch up and in some cases we will work directly with developers to help with recovery. The issue did not cause the loss of any data or potential exposures.”

Potential exposures continued to be logged even when the bug was present, Google said, adding that Apple devices were unaffected.

The UK government initially developed its own version of a contact tracing app, choosing to ignore the Exposure Notifications system which was co-developed by Google and Apple.

However, the government's own app did not work as expected on smartphones running Android, nor on those running older versions of either Android or iOS.

A newly developed app using the Apple/Google system finally launched in September, months after the government’s original projected launch date.