First Ads<\/strong><\/h2>\n\n\n\nSeason two, episode 22: How Does Google Maps Do It?<\/p>\n\n\n\n
At one point in season 1 of this podcast, I was interviewing Luis von Ahn, the creator of Captcha, that website-access test. And during the conversation, he volunteered this opinion: <\/p>\n\n\n\n
Luis: By the way, you know, like Google Maps is an amazing piece of software, by the way. I think it\u2019s one of the biggest, you know, GPS and something like Google Maps is one of the pinnacle of achievement of humankind. <\/pre>\n\n\n\nDavid: We\u2019re doing an episode of this<\/em> on Google Maps! <\/pre>\n\n\n\nLuis: Yeah. It\u2019s amazing. The whole thing. <\/pre>\n\n\n\nOne of the pinnacle achievements of mankind, huh? A phone app?<\/p>\n\n\n\n
And yes\u2014I have wanted to go behind the scenes of Google Maps since the day I dreamed up this podcast. And today is the day.<\/p>\n\n\n\n
Google Maps is one of the most widely installed apps ever made. As of 2021, this app was on ten billion phones. <\/em>A billion people a month use it. A billion.<\/p>\n\n\n\nAs you probably know, Google Maps is great for giving you driving, or walking, or biking directions. But from its first appearance on phones in 2007, it\u2019s aspired to be a lot more than that. Here\u2019s me in a New York Times video, gushing about the iPhone app when it debuted:<\/p>\n\n\n\n
DP: It\u2019s the new Google Maps app for iPhone. The design is clean and modern. Street View lets you see what any address looks like, and Compass view lets you look around someplace without actually being there. Everything is built in: Points of interest, reviews, photos, even making reservations, and the public transportation feature is just amazing.<\/pre>\n\n\n\nNow, if Luis Von Ahn is right, that this app is one of the pinnacle achievements of mankind, I think this is why: Because the whole thing is an inconceivably huge exercise in data wrangling. <\/em>A maps app requires a massive electronic database of road maps; another database of satellite photos of the whole world; a third database with details about businesses; and so on. If you\u2019re Google, you have to stitch all of these data sets together seamlessly.<\/p>\n\n\n\nThat\u2019s hard, but not as hard as keeping it all updated. Forever. <\/em>This is the part that makes me nearly pass out to contemplate. You can never rest. I just\u2014I just don\u2019t know how that could be possible. Thousands of businesses open and close every day. Roads are built. Roads are washed out or closed for construction. Buildings go up. Buildings come down. Trying to keep on top of all that sounds like my version of hell.<\/p>\n\n\n\nPHILLIPS: I love to talk about the map being alive, you know. So, David, think about \u2014it\u2019s changing all the time. It\u2019s\u2014roads can change. I mean, think about that four-lane road that now has two lanes because now there are cycling lanes added to it. Even speed limits change. <\/pre>\n\n\n\nChris Phillips is the general manager of Geo, which is Google\u2019s name for the division that develops geography products, like Google Maps, Google Earth, and Waze. <\/p>\n\n\n\n
PHILLIPS: So how do we keep these things up to date and businesses change? What was a coffee shop is now a laundromat is now a flower shop. What we do is, in order to build a map, we start with\u2014think of it as a layer cake. You know, we are putting together all this imagery that we captured from satellites in our aerial imagery and Street View imagery, and then we start to overlay really important data. And that data we get from what we collect first party, we also work with, you know, thousands of local authorities and transit and mapping services to understand the information that\u2019s out there about a place and the road network. <\/pre>\n\n\n\nQuick glossary of terms here: \u201cfirst party\u201d refers to data that Google has collected itself. <\/p>\n\n\n\n
And you also heard him mention Street View\u2014I mean, what a mind-boggling project. It\u2019s a feature of Google Maps that lets you look around <\/em>at any address. It shows you 360-degree, interactive, panoramic photos, so you can see how fancy or how sketchy a place is before you go there\u2014or without ever going there.<\/p>\n\n\n\nAnd where did these photos of every address on every road come from? They were captured by Google Street View cars, with 360-degree cameras on the roof, driving <\/em>every road in every state in the US. And a lot of other countries, too. And where the Street View cars can\u2019t go, they\u2019ve used bikes, trikes, camels, boats, and snowmobiles. They\u2019ve been driving around, photographing the world for years, and they\u2019re still at it. At this point, Street View includes 280 billion photos from 100 countries\u2014and over 10 million miles of roads.<\/p>\n\n\n\nWe\u2019ll come back to Street View. But Chris was describing how they handle the notion that the world\u2019s geography is constantly changing\u2026<\/p>\n\n\n\n
PHILLIPS: We also bring people into the mix. So our community of users are actually constantly providing information that\u2019s helping us keep, \u201chey, I think the hours of operation are wrong on that business. Let\u2019s edit it.\u201d<\/pre>\n\n\n\nYep. You, too, can make corrections to Google Maps. Look for a button called Contribute or Suggest an Edit. And people do this a lot. <\/em>Like, 300 million people <\/em>send in 50 million <\/em>suggested edits a day. <\/em>The superest of the superfans are known as Local Guides.<\/p>\n\n\n\nPHILLIPS: I get stopped at dinner parties, like, \u201cI\u2019m a local guide at this level. I\u2019ve contributed this many place reviews. I am the expert in my neighborhood, at restaurants.\u201d<\/pre>\n\n\n\nPOGUE: Yeah, you made me realize there must be, like, Google Maps annoying nerds who are very enthusiastic. <\/pre>\n\n\n\nPHILLIPS: Never annoying, just passionate. <\/pre>\n\n\n\nPOGUE: I remember reading an Atlantic article maybe ten years ago, back when it wasn\u2019t so much machine learning, but it was a room full of 300 people or something, manually entering all these changes about the streets and the shops into Google Maps just to keep it current. <\/pre>\n\n\n\nPHILLIPS: We still very much have our operators that help us make sure the quality of the information is accurate. Think of the advanced AI and machine learning as getting so much more coverage in scale than you could get from a person. And the people are actually helping us tune it and make sure it\u2019s right. <\/pre>\n\n\n\nGoogle also uses an army of AI bots to call up <\/em>businesses and interview them over the phone. <\/p>\n\n\n\nPHILLPS: It\u2019s called Duplex. It\u2019s part of our Assistant team, calling millions of businesses and checking in with them with an automated service that says, you know, \u201care you open and closed? Have your hours changed?\u201d <\/pre>\n\n\n\nNow, we start the conversation with getting permission, like, \u201cHey, we\u2019re calling from Google. This is an automated service.\u201d The idea is that we get permission and then you just have a quick conversation. <\/p>\n\n\n\n
And it\u2019s amazing that we can get the latest hours. And even if there were COVID restrictions or do you have accessible bathrooms. Like, things that are really important to keep in that place up to date? <\/p>\n\n\n\n
So this is not just great for consumers, but it helps businesses. Over 250 million businesses around the world. <\/p>\n\n\n\n
POGUE: If I report a change using that little Contribute button, what stops me from deliberately trying to mess you up by making it wrong? <\/pre>\n\n\n\nPHILLIPS: We are using all these advanced techniques to really understand the trust level we have with the feedback. In some cases, depending on the types of information you\u2019re contributing, we will let things through quickly, or we\u2019ll double, triple check our work. And so the moderation technology can have trust built into letting things flow through. <\/pre>\n\n\n\nSo it\u2019s a really, really great example of, where you have the machines that can help us receive these, you know, tens and tens of millions of edits, while also using the people to help check it. <\/pre>\n\n\n\nRemember, I said that we\u2019d be coming back to Street View? Turns out that photographic record of every street in the developed world has a big payoff to Google Maps in another way, too. <\/p>\n\n\n\n
PHILLIPS: Street View is such a cool story. We are using it for so much more than just seeing what a place looks like. So when we are driving, we are also capturing, like, on that street corner, is that still a laundromat or is it now a coffee shop? We are using it to capture changes on street signs. Now it\u2019s something that we use to actually help us update the map. <\/pre>\n\n\n\nAre you starting to get a sense of just how much data is involved in maintaining a representation of the entire planet in an app on your phone? And then keeping it updated? <\/p>\n\n\n\n
Those Street View cars will never <\/em>be done. They\u2019ll be driving forever, just to keep up with the changes. <\/p>\n\n\n\nSo, we now know how they\u2019re keeping the road maps up to date. We now know where they get the photos of the buildings. We know that they get the subway, bus, and train schedules directly from the transit authorities in 800 cities. <\/p>\n\n\n\n
But how on earth does Google Maps know the current traffic speed on a given road? It\u2019s not like they\u2019ve implanted sensors into the pavement all over the planet. And don\u2019t forget, the app also shows you how crowded a restaurant or shop or museum is right now, or will be at a certain time in the future. How does it know that<\/em>? <\/p>\n\n\n\nTurns out the answer to those two questions is, in fact, the same: Google can see the positions of people\u2019s phones <\/em>on that road, or in that restaurant. It measures the movement of those phones, and presto\u2014there\u2019s your traffic speed. It tallies how many phones are in that restaurant, and voila\u2014there\u2019s your crowdedness data.<\/p>\n\n\n\nNow, Google is not tracking you. <\/em>Your phone\u2019s position is anonymous and <\/em>aggregated, meaning it\u2019s dumped into a pool of data with everyone else\u2019s <\/em>phones. And even so, you can opt out of contributing your phone\u2019s position. <\/p>\n\n\n\nThe point is that Google has gotten to the point where it doesn\u2019t just know what the traffic or crowdedness is now; <\/em>it can tell you how bad it\u2019ll be at some time in the future.<\/p>\n\n\n\nPHILLIPS: We take a historical information around what was in, you know, the trends and the patterns that happened before on a Saturday morning versus a Monday morning. You know, that same\u2013 what were the historical patterns of traffic for the people who were driving at those times aggregated and then were able to overlay, okay, what\u2019s happening right now? <\/pre>\n\n\n\nI just gotta mention this one YouTube video I saw: It was a guy who wanted to demonstrate how Google calculates traffic speed. So he piled 99 smartphones into a wagon\u2014like, a kid\u2019s red wagon, with a handle\u2014and he walked along an empty street in Berlin, pulling the wagon behind him. And sure enough: Google Maps reported the traffic as his walking speed. When he stopped in the road, the street turned red, indicating a traffic jam. He literally tricked Maps into rerouting cars to avoid his one-man traffic jam. <\/p>\n\n\n\n
POGUE: But here\u2019s\u2014here\u2019s magic. This is real magic. I and other people have noticed that when I\u2019m entering an address, I have to put in like one digit, and Google Maps proposes the address I want. How does it know? It saves me so much typing. How is that possible? <\/pre>\n\n\n\nPHILLIPS: So it could be defaulting to things that are nearby. You also could be pulling up recent searches that you may have done. <\/pre>\n\n\n\nBut we understand even popular addresses. So what could be really popular as a place that people might be going? <\/pre>\n\n\n\nSo there\u2019s a number of different techniques, and it\u2019s not always one thing, which is part of the magic. <\/pre>\n\n\n\nAnd, by the way, magic that doesn\u2019t cost you anything. I\u2019ve always wondered about that.<\/p>\n\n\n\n
POGUE: How is it that this could possibly be worth it to Google Inc to develop this amazing app and then give it away? <\/pre>\n\n\n\nPHILLIPS: We\u2019re able to monetize with advertising when appropriate. If you\u2019re searching for coffee shops near me, you might get a few coffee shops that are trying to promote themselves in the list of ones that are available. <\/pre>\n\n\n\nPOGUE: Do you make any revenue from licensing the data to corporations? <\/pre>\n\n\n\nPHILLIPS: We do offer it to businesses and enterprises. That\u2019s the other part of my job in the GEO portfolio is, some of your favorite apps have a map inside. Most developers that use it don\u2019t pay. So there\u2019s a pricing approach that keeps it free for most. And, you know, depending on how big you get, you can start to pay. <\/pre>\n\n\n\nSo: At this point, Google has been perfecting and enhancing Maps for 18 years. Every year, it adds more features, and only rarely drops features. <\/p>\n\n\n\n
You gotta wonder: At this point, how much more useful stuff is <\/em>there to add? How is it possible to come up with any more features in an app that\u2019s already packed?<\/p>\n\n\n\nAfter the ad break\u2014you\u2019ll find out!<\/p>\n\n\n\n