Covid 19 tracing app needs ‘1million downloads’

At least a million people need to download the Government’s coronavirus tracker app before it can be dubbed a success, a technology expert says.

About 380,000 people have downloaded the NZ COVID Tracer app, which helps users create a ‘‘digital diary’’ of where they’ve been, since last Wednesday.

That is about 7.6 per cent of New Zealand’s population of 5 million.

Victoria University computer scientist Simon Mccallum said he expected download numbers to be high but so far, they were not good enough.

‘‘You’d want around 1 million to 2 million people to have downloaded the app before you could start saying that you’re fairly confident everyone is recording where they went,’’ he said.

But University of Auckland research fellow Dr Andrew TzerYeu Chen said New Zealand was going to be a country led by manual contact tracing, not an automated system with the Bluetooth proximity tracking.

‘‘Overseas the estimates are around 60 percent of the population needing to have the app, so in NZ even a very low number will be good,’’ he said.

Singapore has been using a bluetooth app called Tracetogether, which logs contacts who come within two metres of each other, and Australia uses a similar app called Covidsafe.

In Singapore, one in four people – 25 per cent of the population – have downloaded Tracetogether since it launched in late March.

Australia’s uptake of Covidsafe is 24 per cent, with six million downloads out of a total population of 25 million.

Two million of those downloads were in the first 24 hours of its launch on April 26, according to overseas news reports.

Chen said the best proxy for measuring the success of the NZ COVID Tracer app is contact tracing time.

‘‘This is the time from when the Ministry of Health finds out about a case of Covid-19 to when they’re able to contact people to tell them that maybe they should stay at home,’’ he said.

‘‘We want to get that number down.’’

A Ministry of Health spokesperson said there had been 17,000 new downloads of the app since Sunday.

The Ministry of Health said there had been 17,000 new downloads of the app since Sunday.