The Government's new COVID Tracer app was fully released on Wednesday morning, and the Ministry of Health has reiterated that users' privacy is a "major consideration".
Director-General of Health Dr Ashley Bloomfield says the ministry has worked closely with the Privacy Commissioner to ensure the app is secure and safe.
Users' contact information they supply when they register is securely stored with the Ministry of Health on an Amazon Web Services server in Sydney, but any extra data such as check-ins at hospitality businesses are stored on the phone and is deleted after 31 days. This information can only be released if a person needs to participate in contact tracing and they give permission for their data to be made available.
"Privacy has been a major consideration, and we recognise the real importance of making sure that people are confident that their information is kept private," Dr Bloomfield said during a press conference on Wednesday.
"[Privacy is] in fact one of the reasons we have been very methodical and taken our time to get the app out for release. We've worked closely with the Privacy Commissioner."
Privacy Commissioner John Edwards said in a statement he welcomes the new app and New Zealanders should feel secure in downloading and using it.
"I want to assure New Zealanders that this app was created using Privacy by Design principles which put privacy at the foundation of the process," he says.
Dr Bloomfield says in future app updates, there may be bluetooth functionality where users who have been identified as a possible close contact with a new case will have a message "pushed out" to them.
If that update does happen, he says all that information will remain on the phone and won't be sent anywhere.
While the app isn't compulsory to download, Dr Bloomfield says any uptake is "good and helpful".
"The more people that use it and download it onto their phones the better, because it just gives us another way of making sure we have up-to-date contact details and then able to push the message out to people if they are identified as a possible close contact.
"At this stage, the main point is to get people registered, downloaded with the app. And then it does have benefits to them… Most people know when they've been at home and who they've been with or when they've been at work. So this is when they're visiting other premises, retail outlets and hospitality venues in particular."
Over 92,000 people have already registered and the first update ironing out the app's bugs will be released on Wednesday afternoon, he says.