It's not evident from the way his hair flops casually down and across, nor from his equally relaxed demeanor, but John Hanke is one of Google's most important idea men.

The entrepreneur is coming up on his 10th year at Google. Over his decade at the search giant, Hanke turned his old startup, Keyhole, into Google Earth and took charge of the company's Geo division, which produces indispensable products like Maps and Street View. But Hanke thinks there's more to geolocation than finding out where you are or where you'd like to go. There used to be a kind of serendipity in getting lost, and Hanke wants to recapture that feeling, but without all the scariness of being in an unfamiliar place.

That's where Field Trip comes in — an app for your smartphone that notifies you when there's a point of interest nearby, such as a historic statue or a restaurant that got a good review from a local blog.

Hanke and I sat down at Google's Washington office Friday to discuss Field Trip and the pace of innovation at Google.

Brian Fung: Tell me about your previous work on the Geo team and how that might have shaped what you're working on now.

John Hanke: When we first launched Google Maps in 2005, one of the big things was plotting information on top of the maps — mashups and mashup sites. It changed the Web in a lot of ways, and it became a popular thing to do to put user-created information on a Google Map. There was one specific example, living in the Bay Area, going back and forth to Lake Tahoe for skiing. It's a long drive on Highway 80 — it's a straight shot along the freeway, but you want to stop along the way because it can be a brutally long drive, especially if there's traffic. And somebody had made this map of all the great places to stop along 80 on your way back and forth to Tahoe. I was trying to use that on my phone as we were driving — it was a mess. I was trying to navigate around that information, and find the pins on the map, and where I was at that point in time, and the insight was that, in many cases when you're out in the physical world, you want geo-referenced information but you don't really need a map because you're already in that location. You're already there. What's interesting to you, maybe, is the information that's tied to that location. So the idea was to strip away everything but the bare essence of the useful data and present that in a way that's easy to get to. With Field Trip, I spend a lot of time thinking about maps and what goes on top of maps, and what could be useful in a mobile setting.

BF: As people have been using the app, what kind of lessons have you drawn from that behavior?

JH: Ranking information is really important. We're showing you a notification on the phone, so we want to be sure that's quality information, that it's relevant to you. The reason for launching on the phone . . . was to start getting signals about what information is useful or not. So whenever you get a card, you can flag something and save it for later. That's a signal to us that a card has a certain interest to you. That'll affect whether we show it to people in the future. Sharing, that goes into it. Scoring. There are various kinds of feedback tools . . . people can indicate whether they want more or less content from a certain publisher. We pay attention to interactions, including "Did you read the whole thing?" and "Did you look at multiple photos?" For user interfaces where you have minimal room for UI, it's important to serve up the right piece of information first.

This reminds me a little bit of Google Now in that when you arrive in a place, the app shows you what restaurants and movie theaters are around. What kind of relationship is there between Field Trip and Google Now?

JH: They're kind of cousins, I guess. Google Now does a little bit with location in that they show the restaurant cards. If you look at it as a Venn diagram, there's a bit of overlap there. They're billed as automatic assistance. What we're exploring more deeply with field trip that might — that probably will make its way back into Google Now at some point is the rest of that location-oriented information, things like history, architecture, shopping, design, urban restaurants.

BF: Have users tried to suggest places that should be included as cards?

JH: They have, but there's no direct way to do it. What we try to do instead is to have them point us to publishers that should be part of it. When we started the app, we felt the [user-generated content] of sites that you would go to that say, "write a review of this restaurant," or Wikipedia-style things that say, "write up all the interesting places in your neighborhood" — there are so many of those, and it's so noisy. People are continuously being asked to become authors and do work for sites. I didn't want to add another one of those to the world. I noticed that there are also great local blogs that are covering this stuff in a local way, and it made more sense to direct people to these publications than to re-create that through user-generated content, which is often of highly variable quality.

BF: So if you take this to its logical extension, we're looking at kind of a Yelp-killer?

JH: [Laughs] Don't say to Jeremy [Stoppelman, Yelp's CEO] that John Hanke is trying to build a Yelp-killer! I think it's different than that. I think there's a component to it that's about restaurants, but I don't know that anyone out there is really doing architecture or history or art, cool local stores selling locally made goods. Detroit was one of our pilot cities. I'm interested in people moving back into cities, reclaiming cities, retaking over neighborhoods. That idea of surfacing these little hook hope spots within cities, that's kind of where we're coming from. There's some overlap with Yelp, but I think it's also doing something new.

BF: So, you have all of this information loaded into Field Trip. Are there types of information you haven't gotten around to including?

JH: Things that are real-time, I think, could be interesting. Things that are changing, things that are moving. I'm interested in public transportation and the intersection there. There's things that move around. Food trucks move around; it's harder to deal with that from an engineering point of view, keeping track of things that are never in the same place. For an application like this, that's an area that hasn't been tapped.

BF: We can't talk geolocation without discussing privacy. What location data does Field Trip use, and what does it store?

JH: The application is reporting back periodically, "John is at this location, John is at this location, John is at this location." Field Trip is not storing each of those points. Field Trip only makes an entry in the database that persists when a card is shown to you. Then we say, "What story is that? Oh, the Thrillist write-up of such-and-such restaurant was shown to you." Now, the set of cards that was shown to you, because they each have a location associated with them, that could be like a course coarse map of your location. That's kind of the worst-case scenario, right? By knowing what cards I've seen and what cards you've seen, someone would know you live somewhere in the northwest section of Washington, D.C., and I live in the Bay Area of California. That's the tradeoff. It's, "Are you okay with Google having access to that level of information about me in exchange for using this service?"

BF: One of the things Google is becoming known for is killing off projects that it's no longer pursuing, Google Reader being a big example. Did you ever worry that your project was going to be put under the knife, so to speak?

JH: You're always worried whether your project is going to be successful or not. But, I mean, what sort of happened was a natural cyclical process where the company had a very liberal policy of letting a thousand flowers bloom. And then a thousand flowers bloomed, and then there was kind of a culling process to create a more unified, simple, elegant user experience, and some of those projects that didn't have user traction were retired so that the engineers could focus on making new things or work on the bigger things. I think it was needed; I think it's been good for the company to focus in. I think that process of starting things and combining them, and starting things — I think it's natural.