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Ep. 1: Expii's Po-Shen Loh Details NOVID Contact Tracing App

Summer of 50 PGH Tech Stories

Expii's Po-Shen Loh gives all of the details on developing the Novid app -- an anonymous contact tracing app for COVID-19. NOVID is the first completely anonymous COVID-19 contact tracing app published in the USA which uses no personal information: no GPS, no phone number and no e-mail. Summer of 50 PGH Tech Stories is powered by Comcast! Learn more about Beyond the Laptops at


Hey everybody, this is Jonathan Kersting. And this is our first episode of the summer of Pittsburgh tech stories, hanging out with Comcast and making this happen. They saw some of the cool work I was doing with your tech by radio one mic stand, and they're like, let's tell another 50 stories over the course of the summer about all the great entrepreneurs, all the technologists, all the people in Pittsburgh's tech ecosystem that are just doing awesome kick butt. And while we do it, we're trying to raise a little money for the for the neighborhood allies and neighborhood allies, excuse me, for the beyond the laptops initiative, because we started that way back in March when the whole COVID thing broke out. We've raised almost, I think, more than $300,000 today, getting a lot of us into underserved students hands, we want to raise some more money by doing this and raising a little bit of awareness. And so to kick this thing off, I really can't think of a cooler person for us to be hanging out with to start our summer stories and hanging out with Po-Shen Loh from Expii. This guy is like he's on fire mode. Submit, really is anybody people I'm like, we need like 1000 more people in Pittsburgh. I'm glad we have one. Too generous, you're generous.

You're, you're building some really cool stuff. And what's cool is some of the stuff you're doing is just it's so behind the scenes that people would sometimes would never even know. And that's why I'm so excited to kind of tell your story a little bit because people are gonna be amazed. What's your background? What brought you to Pittsburgh? What keeps you in Pittsburgh? We're gonna jump into XP and really nerd out on you guys are developing the first anonymous contact tracing app for COVID. 

Wow. Well, thanks very much. First of all, it's a it's a real pleasure to be on this show. I think that what you guys do is fantastic. So I'm actually very honored to be on this show to chat with you about my background. I'm actually just a math guy. I mean, my background is I like to think about mathematics. I like to think I also like to try to find ways to help everyone understand math. And that's because I want to let everyone make better, clearer decisions whenever they're trying to figure something out. Whether that's something as simple as, what should I do to organize my business? Actually, that's not very simple at all. That's hard one, man.

That's pretty hard. But I was gonna say the other one is calculus. I would love to learn calculus again.

We'll get we'll get that. All right. We'll get to that. We'll get to that on all of our products at some point, too. But what brought me to Pittsburgh was actually Carnegie Mellon University's ecosystem. And of course, not just Carnegie Mellon University, but the fact that this city as a whole actually has a lot of innovation hotspots inside it. So I mean, I'm actually attracted by potential. And so when again, yeah, when that when I came here, actually, I came here to Carnegie Mellon. And the first thing that I did for a few years of my work life, was to try to build up Carnegie Mellon's fame in mathematics. And that was fine. I mean, along the way, we actually even brought the national math Olympiad team to come to kind of get out into Every year, that's what I'm talking about, man, we get very cool brought me here and what what's keeping me here is the fact that about six years ago, I started XP, XP as a social enterprise, which I run, where the primary goal is actually to have as much positive social impact in the world as possible with what we know how to do. And what we know how to do is basically Technology Education. Now, apparently also anonymous contact tracing for COVID-19. But not very cool.

But actually, the common thread between all of those is that they all use math algorithms and technology to try to solve some problem that's quite large in the world, right and why I stayed here. Why I'm very happy to stay here is because I found out that it's possible to find really talented people, really passionate people and really mission driven people to work with to build a small organization like this that can have an outsized impact.

Absolutely. And that's why I'm so glad you're here because I use it in all the levels. And what I love is there's math behind everything at the end of the day, math jam, right? So like, I think before we go into the contact tracing side, and people just need to know a little bit about some of the great coursework that you have out there they are teaching kids math right now. And I just think because like we've talked about that before earlier on tech five radio, and I was just so impressed with it. I think our listeners and our viewers here need to give it a little bit about that. And let's just jump in after that into what's going on with how you're taking math to build anonymous contract racing.

Sure, you bet. Actually, the first thing that we built at expii was to build a free platform for people to learn math and science through ways that there would be different kinds of explanations for any particular topic. That was the key. Everyone has different things that appeal to them. And nowadays we have, you know, we have about two to 300,000 people come through a month, which is that's a lot of learning math, man. Come on.

Yeah, it's okay. We're ambitious. We got ambitions in the sense that you know, the goal is to go to 10 million, but I will say that we you know, me to go a long way I gotta get to work harder. Whoa, come on, we're gonna work hard. You slack. You got it, you got it. But so that's what we're doing. That's the free thing that we do. But of course, it's a social enterprise. So it has to make money somehow. And in fact, what we did is about a year ago, we launched in the United States, a line of online math courses that aren't free, but they are targeted towards people who already find school math. Easy. Let's just say that.

I'm not your target audience, oh, sorry. I can never know you never know. Because actually, the way that the other line of those math courses is running, it actually teaches math in a completely different way, where instead of showing you how to do a problem, and then practicing 10 of them, it actually keeps giving you problems that you shouldn't know how to do. But then it gives you hints along the way so that you start to discover for yourself how all of that fits together. And also give explanations to actually Of course, very quick. That second chorus actually that's actually what funds a lot of what we do, because of the fact that it well it happens to be fairly popular in the sense that if you're looking for a course for students are in the top 10% of middle school algebra, for example, those courses are hard to find. And so we actually just put out a video based online course that pays for everything that we do. Cool, man, I absolutely love it. That is awesome. And I love the fact that you're eating up the kids that are finding math pretty easy. You're giving them the really good math problems, right? You see, we're doing both right. So the goal that I have really is to help everybody find that math is easy. And so we have two lines. One line is just for general public to bring people into the world showing lots of different ways of understanding various math and science concepts. And then we have the other one, which is not free, but for people who sort of already got it. So it almost is a it's one. I don't want to call it Robin Hood, because we're not stealing from anyone. But it's almost like a system where people who already have that's where the revenue is generated, and then we use that to fund everybody else. Absolutely.

That's so cool. So let's jump into what's going on with this contact tracing app because obviously COVID hit like about 14 weeks ago, in a building something building something like this. pretty intense. And obviously you were inspired because you knew there was a there was a there was a problem. You knew there was an answer. And it was getting involved in that tells the story and what got you into this.

Right? Well, the story is a bit weird because as I just said, we were doing this online math course and the online stuff blew up. everyone buys it online math courses. So when this all started to happen, I just assumed that my life would go towards online and figuring out how to do things that were online. But there was a catch. So my PhD was actually funded by a group called the Hertz Foundation. The hertz foundation is an organization that was founded by the same hertz as hertz rental car company. Oh, boy. Yes, by the way, he was also the founder of yellow cab, which is why Kurt's logo is yellow. That's why the yellow compare I like this. Yeah, okay. But so the deal is this guy. He actually also was not very far removed relationship wise from the people who were in the Manhattan Project, which were the scientists and engineers that came together in the effort to stop World War Two. And so in the height of the Cold War, you found this This fellowship program to pay for scholarships for people to do PhDs. And the thought was, they might need manhattan project number two to build the Super Mega bomb. And so actually everyone who was funded by this would also get, you get funded, you get a free PhD. But then also you sign a moral agreement that says that if there's ever a moment of national emergency, you'll come together to help. Ah, so this this exists every year. Now, I believe it. Yeah. Right. So every year 15 people across the US are picked. And they're kind of picked by very careful process to find some experts in Engineering Physics. So like often multidisciplinary experts. Yeah, they sign this thing. And so there's this bank of about 1000 people in the US who you know, could be mobilized, you can be mobilized any minute poll, you don't know it.

So you see, I'm actually one of them. So I'm actually okay, but when I was when I signed this thing, I actually wasn't thinking we need more bombs, like nobody needs. Yeah, exactly. Right.

We got enough of those actually, all of us thought that we probably wouldn't be mobilized to do bomb making, but rather We'd be mobilized to defuse some kind of an emergency some kind of a real crisis. Okay. And in fact, in the middle of March, this community was informally called to arms by a senior member of the community. Yes, there was a senior member of the community who we all respect, who in the middle of what I'm talking about, keep going. Yeah,

yeah. So he gave us a lowdown on this is what the deal is with COVID-19. It's not just the flu. It's not just something that will only affect people who are elderly are predisposed, like somehow with predisposed to bad conditions. Which, by the way, I'll be honest, in the middle of March, I was kind of ignorant to I didn't really know what was going on. I just missed it. I mean, this is brand new, right and new, right. So I didn't know but he gave us this early. Notice that here's what we're fighting with. And the end of the message, long message ended the message said, If there was ever a moment of national emergency, it is now. Wow. Right? So that was like the call to arms right? on at that point, right. And you're like flying out to the headquarters. That's what that's what everyone else did. So I saw I started to see the people in this community. We got this mechanical engineering guy, he was figuring out ways to make more efficient ventilators. We saw these biology people working on crazy new vaccine ideas that never heard of. And I'm a useless math guy. This is actually what I felt when I got the email. I was like, useless math guy.

That's what I thought. So here's the story now. So I got I got the message. And I thought I'm a useless math guy. Maybe I'll just contribute with on online education during a time when people need it anyway. Yeah, next day, I was reading like,

You slept on it, right?

It was actually my PhD student. I was reading his thesis because he was graduate. Okay. When I got to the second sentence of his introduction, which is about network theory, or researchers on network theory, number theory is like if you have some dots connected by some lines, what could you do with that? Right? It just blew up. it just dawned on me it was like a flash, it was COVID-19 is actually a network problem. Right. In fact, if you use everything we know about network theory, you could stop the spread of COVID-19. Control the whole thing. At that point, I didn't finish reading my PhD students thesis. Fortunately. Graduated Anyway, good. Yeah, no, no PhD students were harmed in this process. But at that point, I suddenly realized that, you know, with this smartphones that we have, you can anonymously collect the network anonymously in a way. But nobody, we don't even know who is this thought and Who's that? Even? It's just a dot, right? Yeah, it's just

a dot. And in fact, it's a dot with an ID number, where the ID number was randomly generated with nothing to do with the person's name, anything when you realized that you could do this. And then I also realized that if you had a network, you could imagine seeing the spread of COVID-19 start, and then just alerting all the people in its path. And you'd basically be able to cut off COVID-19 before it got into, Oh, my gosh, so then I put everything down. I said, if I figured this out, and actually at that time, no one was talking about contact tracing apps.

And all that was really in the game, right? Yeah. So

I was basically like, we know we can do this. And furthermore, we can do it. In a way, where it actually overcomes the biggest problem with COVID, right, so I, as a mathematician, I think about what's the heart of the problem. The biggest problem with COVID is that almost half of the infection spreads before you even feel the least bit sick. That's the unique factor. In the flu, it's less less like 10%. For the SARS one, it was like near zero percent for COVID is nearly half, nearly 50%. And so when I realized that that was the problem, then I realized that what you absolutely have to do to control COVID is to find a way to as it's spreading quickly find anyone else in its path and wonder. And so that's why that's why nobody was born.

Wow, this is so amazing. And so it's taking you what, less than a few months to kind of get to kids. But how close are you to being able to like unveil this thing? Is it that it's running working? What's the status? This is so exciting?

Yeah, actually, we've released this on April 7. So this is now very interesting. All right. Okay. So the thing is that unfortunately, unfortunately, we actually didn't get very simple coverage. It was a bit it was a bit of, I'll say disheartening, except that we don't give up on anything. Wow. Yeah, this is

blowing my mind. You've had this out since April. And no one's checking this out. So what do you do?

Yeah. So here's what was going on. Right. So actually, on April 7, we released a version for Android that anyone could download if they wanted. But then we needed to get officially into the Apple and Google download stores, right actually was a long bureaucratic process. And I can get that. Yeah, we did that. So by by by saying around May 11, we were actually available for public download all over the world through both Apple and through Google. Okay. And ever since then, what we've been doing is we've just been, we've been continually improving it so that we can show people that you know, this is actually the only one that works in the entire world. But what we're looking for is we're looking for coverage so that people will understand the work to go to the App Store. So you download what happens, you download the app, you have it on your phone. So basically, if you've been reporting if you know that you've had it or have it, you just put that into the app or something like that. And then that Then when you're around other people can it'll it'll alert other people that there is something in the area, how can we do something a little bit different from that we didn't want to make something so that you know, as soon as you're around somebody else, they'll be like, Whoa, all right. So this was designed in a way to protect privacy. So the way that it works right now, is that if you install it, at any point, you can press the report positive button. But when you press that, it's like, then your app is done. It's like a bee stings once and it's done, right. So press the report positive at that one moment. And at one moment, only a notification is sent out to anyone that you might have been around during the time that you were contagious in the past. Okay. So it's not that as you keep walking around with the app, right, gotcha. Makes sense. I hear you. Right.

But if you think about what this does, oh, yeah. And there's as you're walking around with the app, what what's going on? Is that from your pocket to other people's pockets, the app is automatically communicating with Bluetooth. Just to say that was the same way Bluetooth earphones right? Yeah, range communication, and then but it does have to communicates with Bluetooth. It also uses ultrasound. It also plays some sound out of the speakers.

Yep. way.

Yeah, yeah. So we use we use Actually, it's ironic we're using the same method that bats use to stop the virus that came from the bats. What happens is that the two phones which are somewhat nearby, Bluetooth alone, lets you know you're somewhat nearby. And that's what other protocols by say Apple and Google are using. But that's not accurate enough to know whether you're really nearby. What we do is then we have one of the phone ask the other phone. Hey, can you go and send me a pulse like a sonar pulse or radar pulse? Yeah, actually more like a sonar pulse. Then we wait to see how long it takes us owner posts to get to us. And then we're like, that's how far away you are.

There's some math going on right there. I'm not calculation. Yes. The same kind of math that you use when you find out how far away a thunderstorm is. Exactly. Lightning and the sound of the thunder. Right. That's what we do.

This is blowing my mind. And this has happened in Pittsburgh. Oh, yeah. Because of you and your team. That's so cool. Yeah,

so actually, the thing about this, this, this latest ultrasound breakthrough is that this, in fact, makes us demonstrably The only app well demonstrates the distances it measures. We have a demo video we threw up on YouTube last, like a few days ago. And what that actually shows is that under a Carnegie Mellon football field, we just have two phones being held up. And one of them senses how far away the other one is three feet five inches. And the fact that we can do that has just proven that contact tracing is possible, because there are a lot of other contact tracing app projects out there, right, just like the Bluetooth signal strength, and up until this point, no one has been able to display on your screen. Hey, that other thing was like this far away from you. Because they weren't sure they just knew it was somewhere around you.

So I find amazing cuz I mean, not only is this like a powerful tool for now, you're managing and mitigating COVID but I mean, this is not gonna be the last time something like this happens, right? So this is a tool kit that we have is a tool in the toolkit that we have that if something else happens, it can be used for the same purpose and company even more Effective you can get in front of it even faster, right?

Of course. I mean, actually, the reason why we're pushing so hard on this is because I mean, something like this some kind of pandemic like this seems to happen every decade or two, right? There was a SARS one. This is SARS two, there were other things, there were things called MERS, there was Ebola. And it's very important that there's some kind of technology that the next time something starts to spread, which by the way, could be next week, because nothing is up. Okay. Next year, maybe we got to recover a little bit first. But yes or no, exactly.

And I'm happy to tell you actually one of the new features that's that's just coming out on this app, because that's, that's actually where we use the network we have. Right? So the principle of this was that we anonymously completely anonymously have this network. And the new thing will let you know how far away on your network these new reports are. Oh, wow. This actually will create a dynamic that I think will stop will significantly slow the spread of COVID-19. And here I'm just gonna ask you a question because I'm curious how you react to this, suppose you had an app that had a display, and the display is measuring it shows like you know, there's you and there's a across this way it says like how how many relationships away like degrees of separation were these positive reports. So when I say relationships away You and I are talking over a video This doesn't count as a relationship, ours is based on same place relationships example example. If you imagine like somebody living in Pittsburgh, you know, if they and their partner work in different jobs, and you know, they live in the same house, but then suppose person a partner has a coworker and that coworker reports positive, then Person A thinks is distance to await notion, right. So imagine, imagine you had a display that has like you, and then all of the distances to how far away people are that you know, have just tested positive, right. And suppose it's animating like a weather radar map. You know, like the weather radar like four o'clock 415 430 Exactly. Do if you saw on this Whether it or not that, you know, here's you, and then there's like a cloud of infections at distance 10. The next day is that next is at 8am. The next day is at seven. And then at six. I'm curious what your response would be as a person. If you saw a cloud coming towards you 10 98765 every day, what would you do?

I'll be heading away from the cloud, man. What's that? I'd be heading away from that cloud. Exactly. All right, rain gear onto upon minute, I'm not going to get wet.

Right. Right. But what I mean is that like, this is like the COVID radar, right? So if you see that COVID radar distance 10 9876. What this does is it lets every single person basically start to really social distance when it really matters. Because Yeah, because because the point is just everyone's human response to Oh, my it's coming is well, let's just be a little bit careful. I don't mean that I have to be hiding in my basement. But just be more careful. Right, I'll just be more careful. And actually, if everybody has this information, it's not that I need to force anyone To act, I think that most people's natural inclination to Oh, this terrible diseases coming towards me is such that as it gets close, you just start to distance. And if you do that, if everyone just does that, protecting their own selves, right,

everybody, it's gonna Wow, that is such a powerful man in this is unbelievable. That's why I was like, there's no better way to start off this series and talking to you. This is some pretty amazing stuff. You set a very high bar here. Oh, our I guess how I have your shoes to film Just saying. I actually do what I do here because I'm inspired by what else has happened in Pittsburgh.

Yeah. So that's why we're glad you're here in Pittsburgh doing this. What else is going on with XP or any next steps when it comes to what's going on with no big deal? What What's next? Oh, definitely. So expii itself because of the summer vacation. We're just using this time to continue polishing so that when people come back in the fall, there can be a good online resource. The other things we were doing with the paid online Courses those actually are blowing up right now because people are trying to find out ways to maybe learn more math or supplement whatever they're trying to learn. Is that what's going on with Nova? Actually the biggest needs we have right now are to connect with people who are local public health authority working on local public health authorities working in governments, because actually, we really want to help and people might not know. And also there are things we'd like to do, we'd like to confirm the positive tests. Right, right now your self report, oh my gosh, if we could work with Allegheny County data, right, you'd be able to really sharpen things up even more. Absolutely. And we can do it anonymously to write. So we're just looking to have a way to work together with public health authorities just to deliver to everybody something that can keep you safe. Another I've explained to you about the feature is, I will hope that everyone watching this would say, I wish I knew how far away COVID-19 was, I want to download the app and see what's going on, man. Yeah.

That's a feature I want to see. I just want to know Do I need to be scared to death in the sense of you know, Great. Again

doing? Yeah, no, that's seriously this is amazing work. It's been an honor to talk to you about this because like, this is what's making a difference. This is what happens in Pittsburgh. You got folks like you, they're solving tough problems that impact the world. Simple as that. And like I said, I can't think of a better person to start off this entire series with and retelling more amazing stories like this Whoa, all summer long. And we're gonna try to raise a little bit of money, the neighborhood allies and to beyond the laptops initially, because we want as many kids as they can connect to their coursework, their schoolwork, and they can connect to XP and do some free math problems and sharpen up their path. Absolutely. Well, it's just amazing stuff. And we couldn't do this without the help of our guys at Comcast back here. They got my back, literally and figuratively so we can tell these stories and get them out there and show Pittsburgh is one hell of an amazing place. Simple as that. A great.

So you're the best, so much fun talking to you.

Thank you real pleasure to talk to you, too.

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