I installed and setup Health Canada's COVID Alert app this morning.

It's really simple to do that. You don't enter any personal information. You just select which province you're in, agree to let it use your Bluetooth, and give it permission to share the random codes that you collect with its servers (more on this below). The app is then active and working. But to be clear, it doesn't collect your location (it doesn't use GPS or location services). It doesn't collect the places or times that you are next to someone who also has the COVID Alert app. And it doesn't know if you're with someone who was previously diagnosed with COVID-19.

Built on top of the private exposure framework that was collectively developed by Apple and Google, the app works by using Bluetooth to exchange "random codes" between nearby phones that have the app. These are anonymous and random codes that are used to track which phones have been next to which phones for any meaningful period of time. The app also uses Bluetooth signal strength to estimate proximity. So it knows how long your phone has been proximate to someone else's (with the app) and how close they got to each other.

That's pretty much all that happens with the app unless you test positive for COVID-19. At that point, you will be given a one-time key along with your diagnosis. The onus is then on you to anonymously self-report on the app. Once you do that, anyone who was exposed -- i.e. next to your phone in the last 14 days -- will receive an alert on their phone via the app. And since the app doesn't know any names or who anybody is, it's of course all completely anonymous.

It's great to see all of this coming together. The private sector worked to build the underlying framework and now you have government building on top of it to deliver public health tools. I know that some or many of you will be concerned about privacy, but that appears to have been very well thought out. If you haven't already downloaded the app, I would encourage you to check it out. It's available for iOS and Android and can be downloaded over here.

The “contact tracing” API that Apple and Google are working on and that I wrote about earlier this month is set to be released on May 1. Given all the concerns around privacy, it’s now being referred to as “exposure tracing.” The idea, here, is to emphasize that it is being designed to trace the coronavirus and not individuals.

To be clear, we’re talking about APIs, and so third party apps will need to be built on top of this tech before we can start downloading anything to our phones. But I am sure that will happen very soon and I will gladly opt in.

It’s also worth mentioning that this entire concept of smartphone exposure tracing only works when Apple and Google cooperate. Whatever apps ultimately get built need to work across both platforms, otherwise there would be far too many gaps in the network. So this — along with the focus on privacy — has become a bit of good PR for “big tech.”

The smart people working on exposure tracing over at Oxford University seem to think that (alongside other interventions) we could stop this virus with only about 60% of the population using an exposure tracing app. (They ran models with a pretend city of 1 million people.) But even at 50% penetration, they believe it could make a meaningful contribution.

These are numbers I think we could easily get to in major cities. Overall, I suspect it could also make people feel a lot more comfortable about going out. And going out is what’s going to be required as we gradually reopen the global economy. How many of you think you will opt in to something like this once it becomes available?

I installed and setup Health Canada's COVID Alert app this morning.

It's really simple to do that. You don't enter any personal information. You just select which province you're in, agree to let it use your Bluetooth, and give it permission to share the random codes that you collect with its servers (more on this below). The app is then active and working. But to be clear, it doesn't collect your location (it doesn't use GPS or location services). It doesn't collect the places or times that you are next to someone who also has the COVID Alert app. And it doesn't know if you're with someone who was previously diagnosed with COVID-19.

Built on top of the private exposure framework that was collectively developed by Apple and Google, the app works by using Bluetooth to exchange "random codes" between nearby phones that have the app. These are anonymous and random codes that are used to track which phones have been next to which phones for any meaningful period of time. The app also uses Bluetooth signal strength to estimate proximity. So it knows how long your phone has been proximate to someone else's (with the app) and how close they got to each other.

That's pretty much all that happens with the app unless you test positive for COVID-19. At that point, you will be given a one-time key along with your diagnosis. The onus is then on you to anonymously self-report on the app. Once you do that, anyone who was exposed -- i.e. next to your phone in the last 14 days -- will receive an alert on their phone via the app. And since the app doesn't know any names or who anybody is, it's of course all completely anonymous.

It's great to see all of this coming together. The private sector worked to build the underlying framework and now you have government building on top of it to deliver public health tools. I know that some or many of you will be concerned about privacy, but that appears to have been very well thought out. If you haven't already downloaded the app, I would encourage you to check it out. It's available for iOS and Android and can be downloaded over here.

The “contact tracing” API that Apple and Google are working on and that I wrote about earlier this month is set to be released on May 1. Given all the concerns around privacy, it’s now being referred to as “exposure tracing.” The idea, here, is to emphasize that it is being designed to trace the coronavirus and not individuals.

To be clear, we’re talking about APIs, and so third party apps will need to be built on top of this tech before we can start downloading anything to our phones. But I am sure that will happen very soon and I will gladly opt in.

It’s also worth mentioning that this entire concept of smartphone exposure tracing only works when Apple and Google cooperate. Whatever apps ultimately get built need to work across both platforms, otherwise there would be far too many gaps in the network. So this — along with the focus on privacy — has become a bit of good PR for “big tech.”

The smart people working on exposure tracing over at Oxford University seem to think that (alongside other interventions) we could stop this virus with only about 60% of the population using an exposure tracing app. (They ran models with a pretend city of 1 million people.) But even at 50% penetration, they believe it could make a meaningful contribution.

These are numbers I think we could easily get to in major cities. Overall, I suspect it could also make people feel a lot more comfortable about going out. And going out is what’s going to be required as we gradually reopen the global economy. How many of you think you will opt in to something like this once it becomes available?