The HSE's 'COVID Tracker' contact tracing app has now been installed by one million people.
The app became available for iOS and Android devices on Monday evening.
HSE boss Paul Reid this evening confirmed the app has already reached one million registered users, less than 48 hours after it became widely available.
Right now I can confirm that we have now reached 1M registered users of the #CovidTrackerApp. The app wont make you immune to the virus but it can help to reduce the risk. Lets keep it going. Please sign up and encourage your network to do so also. @HSELive #COVID19 pic.twitter.com/5EkDaNSUhx
— Paul Reid (@paulreiddublin) July 8, 2020
A number of other countries in Europe and around the world have introduced similar contact tracing apps in recent weeks and months.
Mr Reid earlier today called the Irish launch "by far the most successful launch of this app anywhere in the world".
The app's primary function is to let users know when they've been in close contact with someone who later tests positive for COVID-19.
If someone you were in close proximity for a 15 minutes or longer later tests positive for COVID-19, then you will receive a notification informing you of that.
Users need to enable Bluetooth and keep it on all the time for the app to function as intended.
Officials have said the app - which does not replace the existing contact tracing processes - will be more effective the more people use it.
Health Minister Stephen Donnelly has insisted privacy is "right at the heart" of COVID Tracker's design, with personal data stored on the user's phone rather than a central database.