that the COVID Alert app has been shut down, citing low usage, falling case counts and hospitalizations as well as the lack of PCR testing across Canada.

As of June 17, the app will no longer provide exposure notifications and Health Canada says users can now delete the app.

The app had only been downloaded 6.9 million times and logged 63,117 positive tests since it launched in July 2020. British Columbia, Alberta, Nunavut and Yukon also declined to participate in the app.

Infectious diseases expert Dr. Isaac Bogoch calls the app "a good idea at the time" but says after six to eight months, the low uptake meant that the app "was not really going to be an effective tool."

"It's going to be tough to actually measure the true impact of the app and unfortunately, it probably wasn't as good as we wanted it to be," Bogoch told CTV's Your Morning on Friday. "The app was only downloaded just under seven million devices, which isn't nearly enough for something like this to have any effectiveness. You really need roughly 60 to 70 per cent of a population to have an app like this."

The app worked by keeping track of other users who have been in close proximity to you by using Bluetooth signals. Users who tested positive via a PCR test could receive a one-time key to enter into the app and alert other users that they've been in close contact with a positive case.

This process was sometimes disjointed. If a user was in a jurisdiction that didn't automatically issue a key, they had to contact their local public health unit for one.

But with most provinces now restricting PCR test eligibility to health-care workers, hospital patients, long-term care residents and others deemed to be at higher risk, the majority of users who contract COVID-19 were not able to obtain a one-time key, as keys are not given out after a rapid test, further undercutting the effectiveness of the app

Back in December, John Haggie, Newfoundland and Labrador's health minister, told reporters that the federal government "gave up" on the app months ago, although Haggie later walked back his comments and Health Canada reiterated the federal government's commitment to the app at the time.

In March, Manitoba also ended its use of the app and is no longer distributing one-time keys. Alberta has its own contact tracing app , but the province has announced that this app would be decommissioned on June 23.

To address privacy concerns, the federal government said that the app has no way of knowing the user's location, name, address, phone contacts and the personal information of other app users who were in close proximity.

When the app first launched, the federal and Ontario privacy commissioners conducted a review of the app and gave their support, saying it was "developed with robust safeguards to protect the identity of users."

Bogoch believes some of the steps designed to protect the privacy of Canadians, such as making the app voluntary, may have hindered its success. In Singapore, the adoption rate for the country's COVID contact tracing app is 92 per cent, as using the app was made mandatory to enter many public spaces.

"This app involves people having to download it, and then having to report that they indeed had COVID," he said. "That's just probably not the best way to run it. I'm not even sure if an app-based approach in a place like Canada would be a good idea in terms of an effective way to do contact tracing moving forward just because of how much we do value our privacy."

But despite the app's low uptake, Canada's Chief Public Health Officer Dr. Theresa Tam said it was nonetheless important that innovations like this take place during a public health challenge.

"Not all innovations might work in the different populations, but I think it is good that there was a good go at trying to utilize another tool in the current era of apps to try and protect the population," she told reporters during a COVID-19 media briefing on Friday afternoon.

all data from the app will be deleted, other than aggregated performance metrics which contain no personally identifiable data. 

With files from CTVNews.ca's Sarah Turnbull and The Canadian Press.