More than 200 thousand people have already registered for the new Covid tracker app.
The App was developed by Waterford company Nearform who are based in Tramore.
The HSE app, which is now live, lets people see if they've been in close contact with someone with Covid-19.
It's cost 850,000 euro to develop so far.
It will record if a user is in close contact with another user by exchanging anonymous codes that are held on the users’ phones.
People who test positive for the coronavirus will be able to choose if they want to anonymously alert other app users who they have been in close contact with.
The app will also allow the user to anonymously record information about how they feel every day.
The information stored on the app will not be transferred to a centralised server.
It has emerged that 35 per cent of people identified as close contacts haven't taken up the offer of a test.
For the first time since March, there have been two consecutive days with no reported deaths, while four new cases have been confirmed.
Acting Chief Medical Officer, Dr. Ronan Glynn, says that's a positive development.
The app has been developed by the HSE and the Department of Health, in collaboration with the Government Chief Information Officer and An Garda Síochána, together with technical partners from the Irish private sector (Expleo, Nearform, Information Security Assurance Services Ltd (ISAS), and EdgeScan) and scientific partners from Science Foundation Ireland.
