Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The Hack That Brought Foursquare Back From The Dead

wired.com

Post reply on HN
Print view View original

31–40 of 51 posts

Re: The Hack That Brought Foursquare Back From The Dead

#31

Post by austinl »

A bit of background - "geofencing" has been around in iOS as part of Core Location since version 4.0. Given latitude and longitude, you can pass in a radius and create a circular region (or specify a set and create a rectangle), with callbacks that trigger when the user enters or exits that region.

One of the main points in the article is that it's particularly battery intensive to update the user's location, so there's a trade off between accuracy and battery usage. To try and solve this, Apple created a hierarchy of accuracy constants, which range from "best" to three kilometers, but it's only somewhat effective at preserving battery life.

The other strategy is monitoring "significant changes" in location, based on cell towers/wifi signals. For this, Apple provides a method called "startMonitoringSignificantLocationChanges" if your app needs to constantly monitor the user's location.

From what the article said, Foursquare is trying to improve these methods by creating probabilistic maps so they can draw better regions for each user, and therefore check for location updates less frequently. I'm assuming there are similar methods for Android.

Here's the documentation for one of the main classes in Core Location called CLRegion: https://developer.apple.com/library/ios/documentation/CoreLo...

Re: The Hack That Brought Foursquare Back From The Dead

#32

Post by lnanek2 »

untog wrote: post #2

This problem isn't solved yet. For me at least. I turned on the passive notifications, and they started going off when I was traveling on above ground sections of the subway. Or when I got out by my office. So I turned them off. Somehow Foursquare needs to crack working out when I want those notifications and when they're irrelevant. They should have enough data to do it.

Yeah, I've been using 4sq for years and still do, but just don't have any use for the passive notifications. They only crop up when I'm going somewhere or doing something already. Most amusingly, they've been showing up on flights lately and they are actually correct. Not sure how that even happens since I know Google's WiFi database tends to just have the wrong location for train and plane WiFi in my experience. I'll hop on a train in NYC and it will say I'm in Boston.

Re: The Hack That Brought Foursquare Back From The Dead

#33

Post by lnanek2 »

schnevets wrote: post #20

I always loathed Foursquare because it interfered with social occassions. You and some buddies walk into a location, and suddenly everyone has to take out cell phones. It's relieving to hear that the company's strategy was always to become less obtrusive. I may actually download the new app now.

I've actually found it to be a social benefit myself. Most of the people I go out with use it and we tend to compete and discuss what picture and tagline we're going to use and who is better and who checks in first. Much of the time the conversation later goes on to what cool things our friends did lately or if we can tell it is snowing somewhere better through 4sq or Instagram, often with much showing of the phones to each other.

I guess younger generations build technology into their lives whereas for older people it is just an interruption. Try just friending everyone everywhere you go and eventually you'll have cool people all over the world doing fun things that can start conversations instead of stop them.

Re: The Hack That Brought Foursquare Back From The Dead

#34

Post by vidarh »

justinsb wrote: post #19
raldi wrote: post #10

To save you some reading, the crux of the hack is to consider a weak GPS (etc) signal not as a lack of data, but rather as a source of data in itself: the fact that the GPS signal is weak tells you something about the user's probable location.

Isn't this exactly how location is always done without GPS? Look at the strengths of all the radio signals we can see, and match against known locations? Admittedly it's previously been primarily cell-towers & wi-fi, not GPS signal strength, and I thought most of the previous data had been collected by people that also had GPS, not via foursquare checkins... If not, why does my Android phone ask me to turn on wi-fi t…

Consider that Foursquare has extra data: Checkins.

They know that when certain location data sources provided chertain signals, the user in question checked in at a location with a known map position and known constraints to the location.

There aren't many sources of location data with that extra information.

Re: The Hack That Brought Foursquare Back From The Dead

#36

Post by nisa »

lucb1e wrote: post #5

Page is blank when adblock is enabled. Anyone else having this problem? I just won't read this article now. Not my problem.

Can confirm the problem on Chrome 31 and Firefox 25 - Adblock Plus / Ghostery.

Subscriptions: Malware Domains / Fanboy's Social Blocking List / EasyPrivacy / Easylist Germany+Easylist

Re: The Hack That Brought Foursquare Back From The Dead

#37

Post by frogpelt »

hnriot wrote: post #9
protomyth wrote: post #8

Earlier quoted context omitted.

"if you live in NYC or SF it's a lot more useful than it's been to me" It seems like services that bring people from vast geographic distances (e.g. Facebook, Twitter) have a longer life than services the geo-limit the audience. If you're in NYC, SF, or LA, geo-limited services work due to density, but you the threshold seems to dive after a couple of cities down the list. Color was the ultimate example for me on som…

It's the density that make Foursquare more popular in SF and NYC but rather the demographics of those areas, modern, high tech centers of urban sophistication. The fly over states are more concerned with the latest developments in pickups and gun racks to care much about checking in at the hottest espresso bar.

While it's true that people in rural areas often don't care about the same things that people in big cities care about that doesn't mean they are oblivious or opposed to new technology.

I have a friend who is a commercial poultry farmer in rural Mississippi. He can turn on his chicken house feeders from anywhere in the world with a smart phone app. Some of the coolest technology being built is farm-related. People, no matter where they live, just want technology that makes their lives better in some way.

Re: The Hack That Brought Foursquare Back From The Dead

#38

Post by drcube »

lucb1e wrote: post #5

Page is blank when adblock is enabled. Anyone else having this problem? I just won't read this article now. Not my problem.

Firefox 24 on W7 with adblock plus, it works for me. But I also have noscript with 14 out of 26 scripts blocked on that page. That probably helps.

Re: The Hack That Brought Foursquare Back From The Dead

#39

Post by VLM »

mintplant wrote: post #27
mseebach wrote: post #22

Earlier quoted context omitted.

>> It showed how strong the GPS signal was at the time, how strong each surrounding Wi-Fi hotspot signal was, what local cell towers were nearby, and so on That quote struck me as very strange. Why would they collect all that data in the first place, anyway, if not to do exactly this?

Foursquare has measures in place to prevent people from gaming the check-in system--to keep people from faking check-ins and gaining badges and mayorships that they didn't earn. From what I've gathered, they collected this information originally to prove that someone was really at the location where they claimed to be.

"to keep people from faking check-ins and gaining badges and mayorships that they didn't earn."

And yet, people claim bitcoins are worthless.

Re: The Hack That Brought Foursquare Back From The Dead

#40

Post by protomyth »

GuerraEarth wrote: post #30
protomyth wrote: post #6

Earlier quoted context omitted.

Using Safari with ad blocker and I can see the content. I really didn't want to install an ad blocker but the damn pop-ups were getting too much.

Even worse are the audio ads.

No doubt. I wonder how many people have the sound off on their computer's until they actually need to hear something?
Post reply on HN