The German government on Tuesday urged people to download a new smartphone app that warns users if they might have been in close contact with COVID-19-infected individuals.

Helge Braun, chief of staff for Chancellor Angela Merkel, praised the "Corona-Warn-App" as the frontrunner in its field.

The app was, he said, "not the first warning app worldwide, that has been put forward, but I am quite convinced that it is the best."

"To download and use it is a small step for each one of us, but a huge step in the fight against the pandemic," he told a launch event for the app in Berlin.

Track-and-trace apps have been touted as a high-tech tool in the effort to track and control COVID-19 infections. Experts say finding new cases quickly is key to clamping down on fresh clusters as countries relax restrictions while seeking to avoid a second wave.

"Fighting this virus and containing it is a team game," Health Minister Jens Spahn told German broadcaster ZDF, adding he would be happy if "many hundreds of thousands, ideally many millions," would download the app.

"This is a plus for everyone who downloads it, and for others," said Spahn.

 The app does not log the whereabouts of individuals, meaning authorities cannot spy on the users. It recognizes only which other app users are currently in the vicinity. The system works via Bluetooth, a wireless standard that enables devices to exchange data at close range.

Read more: Will coronavirus be the deathblow for German city centers?

The minister refused to say how many people would need to use the app for it to be considered a success. He also dismissed a study released by Oxford University that claimed that such an app could only be useful if in use by more than 60% of the population. 

Spahn said the performance also depended upon exactly who was downloading the app, and he pleaded with public transport users in particular to use it. Their participation would make a "qualitative difference," Spahn said.

Late, but worth the wait?

Meanwhile, Spahn defended a delay in the introduction of the app, which has been a source of criticism for the government.

"There's a lot of work involved in it, so it just needed a few days longer. But we are within the cost and time plan," he said.

The German Retail Association (HDE) also urged members of the public to use the app for the protection of staff and shoppers.

"The more people use the app, the more effective it will be at preventing the further spread of the coronavirus," said HDE President Josef Sanktjohanser. "The app is a further important step to ensure more safety in everyday life."

Historical concerns over privacy

The German government insists users will have full control over their data, but concerns remain. Both the communist regime of East Germany and the Nazis amassed large amounts of information about their citizens, and concerns about government snooping remain. 

A recent poll by public broadcaster ARD found that slightly more Germans — 42% — said they would use the tracing app than the 39% who said they wouldn't. Others said they didn't have a smartphone or hadn't made up their mind.

The German government says the app cost €20 million ($22.7 million) to develop, and that it will need about €3 million per month to operate. 

Germany has so far recorded some 190,000 cases of COVID-19, with some 8,800 deaths.  

rc/aw (AFP, dpa, Reuters)

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