A new smartphone app that alerts users if they have come into close contact with someone who has tested positive for the novel coronavirus went into service on June 19.

The health ministry is offering the app free of charge on mobile app platforms. 

“I hope that as many people as possible use this app," said Yasutoshi Nishimura, the economic revitalization minister, at a news conference on June 18. "We are preparing the system to allow users who received the contact notice to undergo testing for the coronavirus smoothly.”

The app records smartphones that come within a radius of 1 meter for more than 15 minutes by exchanging anonymous IDs.

If an app user tests positive for the novel coronavirus, the notice “you had contact with a virus carrier” will be sent to the smartphones of everyone who had close contact within the past two weeks. 

The app uses Bluetooth wireless technology and does not collect personal information, such as names and phone numbers, to ensure privacy. It also does not record location information.