First Minister Arlene Foster has said she is "proud" that Northern Ireland is the first UK nation to have its own contact tracing app.
StopCOVID NI, which was set to be launched on Friday, was released for download from Apple's App Store and on Google Play on Thursday.
"It will work in an interoperable way with the app in the Republic of Ireland and indeed any apps that are brought forward in the UK nations," said Mrs Foster.
StopCOVID NI has several features for logging details of those experiencing symptoms of the virus and had hundreds of downloads when first released.
It is intended to supplement the phone-based contact tracing programme already in place and will identify those at risk of infection.
Health Minister Robin Swann urged the public to download the app, which comes ahead of the roll out of a public information campaign to encourage take up.
“Deploying this world leading technology can prove a major factor in helping our efforts to curb Covid-19 and prevent its spread. Its potential to be a game changer will, however, be totally dependent on the support of the Northern Ireland public," he said.
It comes as eight more positive cases of coronavirus have been detected in Northern Ireland, the Department of Health said.
No new deaths were recorded, leaving the total in the region at 556, according to official figures.
More than 141,000 patients have now been tested,with 5,938 registering a positive result.
On Thursday, Chief Medical Officer Dr Michael McBride said "strengthened" evidence supported extending the period of self-isolation from seven to 10 days for those who test positive for Covid-19.
The change, which was announced by the UK's four chief medical officers, came as ministers work to avoid a resurgence of the virus in autumn and winter months.
Here's how Thursday unfolded: