Bluetooth upgrade to NZ COVID Tracer app to boost contact tracing while protecting privacy
Hon Chris Hipkins
Minister for COVID-19 Response
11 December 2020
- Additional tool to support existing contact tracing processes
- Privacy is protected
- Does not replace the need to scan QR codes
Contact tracing in New Zealand will get a substantial boost from 10 December with the addition of Bluetooth tracing to the NZ COVID Tracer app, Minister for COVID-19 Response Chris Hipkins said today.
“Kiwis deserve a summer break more than ever this year but we cannot take our eye off the ball. The prospect of another outbreak should serve as a rock under our beach towels. That’s no bad thing,” Chris Hipkins said.
“As summer approaches and Kiwis take holidays and travel more around the country, this new Bluetooth functionality adds to the tools we already have and improves our chances of getting on top of any potential outbreak quickly – as long as we use them.
“It allows app users to receive an alert if they have been near another app user who tests positive for COVID-19.
“But it’s vitally important that New Zealanders see Bluetooth as an additional tool that will help to speed up contact tracing. We need to continue to scan QR codes wherever we go, and businesses, services and public transport providers must keep displaying their QR Code posters at all alert levels.
“QR codes allow us to create a private record of the places we’ve been, while Bluetooth creates an anonymised record of the people we’ve been near.
“Combined, they complement the work done by our public health units and the National Investigation and Tracing Centre to rapidly identify and isolate close contacts. That continues to be the primary method for contact tracing in New Zealand,” Chris Hipkins said.
How it works
Bluetooth tracing in the NZ COVID Tracer app implements the Apple/Google Exposure Notification Framework, a secure protocol for transmitting Bluetooth data between devices.
If you choose to enable Bluetooth tracing on your phone, it works by exchanging randomised ‘keys’ with other phones that are also using Bluetooth tracing. The keys do not include any information about who you are or where you were.
When an app user tests positive for COVID-19, they can choose to alert other app users who may have been exposed to the virus. This involves uploading the ‘keys’ that their phone has broadcast since they became infectious.
If your phone sees that one of the keys it has collected is listed in the notification, you’ll receive an alert together with advice on what you should do next to keep yourself and your whānau safe. The Ministry of Health will not know you have received an alert unless you choose to get in touch for information and advice.
“We need as many people as possible to use the app, so it’s incredibly important that New Zealanders know they can trust the app with their personal information,” Chris Hipkins said.
“Maintaining privacy has been a top priority throughout the development of the NZ COVID Tracer app, and this doesn’t change with Bluetooth tracing. All the contact tracing information you collect with the app is held securely on your phone, and it’s always your choice what information you choose to share.
“The app has been endorsed by the Privacy Commissioner, and the Ministry of Health is releasing the source code so New Zealanders can see for themselves how their information is managed.”
Chris Hipkins said the Government recognised there are many New Zealanders who do not have access to a compatible smartphone. While no decisions have yet been made on any wider rollout of the proposed contact tracing cards, there is potential for the cards or other wearables to form part of a broader system of interoperable technologies.
“The recent community trial of the cards with the Te Arawa COVID-19 Response Hub has highlighted that a partnership approach to any future rollout of cards or wearables will be essential to increasing community trust and participation with contact tracing technologies.”
NZ COVID Tracer will update automatically on around 10 December for most users, or it can be manually updated through the Apple App Store or the Google Play Store at that time. Bluetooth tracing will be turned off by default, but app users will be asked if they want to enable it when they next open the app.
- Ministry of Health:
- Unite Against COVID-19 website: www.covid19.govt.nz/bluetooth-tracing
- Source code: https://github.com/minhealthnz
What is the benefit of enabling Bluetooth tracing on the NZ COVID Tracer app?
Bluetooth has the potential to speed up contact tracing by enabling people to be more quickly alerted if they have been nearby someone who has tested positive for COVID-19.
There are currently around 2.4 million registered users of the NZ COVID Tracer app, of which approximately 90 percent will have phones that are compatible with Bluetooth tracing. This provides the critical mass of users needed for Bluetooth tracing to detect a significant proportion of ‘close contacts’ between individuals.
Is Bluetooth tracing limited to the NZ COVID Tracer app?
The Apple/Google Exposure Notification Framework also has the potential to be implemented in wearable devices such as cards or wristbands or other personal devices that have Bluetooth.
Will Bluetooth tracing detect all my close contacts?
No, Bluetooth tracing will only collect randomised ‘keys’ from other nearby app users who are also using NZ COVID Tracer with Bluetooth tracing enabled. Not everyone uses the app and some app users will not have Bluetooth tracing enabled.
Is Bluetooth tracing mandatory? Bluetooth tracing is optional but recommended. Once the NZ COVID Tracer update is installed, and if the phone is compatible with Bluetooth tracing, the app user will be prompted to decide whether to opt in.
Along with QR code scanning, Bluetooth tracing is another tool in the toolkit to help keep us safe from the virus by enabling rapid and effective contact tracing. QR codes allow us to create a private record of the places we’ve been, while Bluetooth allows us to create an anonymised record of the people we’ve been near.
Will Bluetooth tracing use up my mobile data?
Bluetooth doesn’t use any mobile data because it does not involve accessing the cellular network. Bluetooth is a form of wireless communication that enables phones and other devices to talk directly to each other.
However, while the Bluetooth function itself does not use any data, the NZ COVID Tracer app does use a very small amount of data when your phone checks for contact alerts, and when anonymised analytic information is sent to the Ministry for reporting purposes.
Will Bluetooth tracing drain my battery?
The app uses Bluetooth Low Energy (BLE), which is designed to use considerably less power than Classic Bluetooth. As a result, the impact on phone battery life will be minimal.
If an app user thinks their battery is draining faster than usual after enabling Bluetooth tracing, they can check this by looking at their phone’s settings to see how much of the battery usage relates to each app installed on the phone.
If you think the app’s battery usage is excessive, please contact the NZ COVID Tracer support team at firstname.lastname@example.org or on 0800 800 606 so we can look into the problem. You will need the following information:
- Percentage of battery used
- The make and model of your phone
- Your phone’s version of iOS or Android
Do you need the NZ COVID Tracer app if you have Bluetooth enabled on your phone?
Yes, Bluetooth tracing will only work if you have a compatible device with the NZ COVID Tracer app installed.
Does the NZ COVID Tracer app need to remain open for Bluetooth tracing to work?
No, the Bluetooth tracing function is part of the operating system of your phone, which means you don’t need to keep the app open.
Will NZ COVID Tracer still send location alerts?
You will still receive a location alert through the NZ COVID tracer app if you scan the QR code for a location at around the same time that it was visited by a person who has tested positive for COVID-19.
Can I receive both a Bluetooth alert and a location alert for the same ‘exposure event’?
You may receive both a Bluetooth alert and a location alert if you were nearby a person with COVID-19 who has been using Bluetooth tracing and if you also scanned the QR code at a location visited by that person.
The information and advice contained within a Bluetooth alert takes precedence over any location alert because the risk of exposure from being nearby someone who has COVID-19 is generally higher than the risk associated with visiting the same location.
Do all phones support Bluetooth tracing?
The Apple/Google Exposure Notification Framework (ENF) is built into the operating system of all phones running iOS 13.5+ or Android 6.0+. Android devices must also support Google Play Services and Bluetooth Low Energy in order to use Bluetooth tracing.
Phones with older operating systems cannot provide Bluetooth tracing because they do not have the ENF built in. However, the ENF is a protocol that also has potential to be used in other devices such as cards or wristbands or other personal devices that have Bluetooth.
If your phone is running iOS 11 or later then you can still use the NZ COVID Tracer app to scan the QR codes and add manual entries to your digital diary, and you will still receive location alerts if you have them enabled.
Can people with older phones still use NZ COVID Tracer to scan the QR codes and add manual entries to their digital diaries?
Yes, you can still use all other functions of the NZ COVID Tracer app if your phone has:
- iOS 11+ or
- Android 6.0+ (for devices that also support Google Play Services)
If I use Bluetooth tracing will the Government, Apple or Google have access to my Bluetooth data?
No. The Ministry of Health’s implementation of NZ COVID Tracer is decentralised, which means your Bluetooth data and digital diary are stored securely on your phone and are controlled by you.
If you test positive for COVID-19 and choose to send a Bluetooth notification, this does not involve transmitting any identifying information. The only information contained within the notification is a list of the ‘keys’ that your phone has broadcast when you were infectious.
NZ COVID Tracer has been endorsed by the Privacy Commissioner and the Ministry of Health has also released the source code so New Zealanders can see for themselves how their information is managed.
Will the Government, Apple or Google be able to track my movements if I use Bluetooth tracing?
No. Bluetooth tracing does not involve location tracking of any kind.
Bluetooth tracing works by generating randomised ‘keys’ and exchanging them with other nearby smartphones. The keys don’t contain any information about who you are or where you were, which means no personal or identifying information is exchanged.
Your Bluetooth keys are stored securely on your phone, and only your phone knows which keys belong to you.
Last updated: Friday, December 11, 2020