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The Hack That Brought Foursquare Back From The Dead

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Re: The Hack That Brought Foursquare Back From The Dead

#22

> Foursquare already had a massive database of check-ins — location information about the places its users most liked to go. And this data didn’t just include the place where someone had checked in. 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. Leveraging this data meant that Foursquare could still grab a good…

>> 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?

Re: The Hack That Brought Foursquare Back From The Dead

#23
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…

The primary purpose of WiFi to enhance location information is to bootstrap the download of current GPS orbits (the ephemeris) [1].

More advanced techniques relying on radio signal strengths, RTT time, and other observables [2] are being developed but I don't know of any in widespread use. I wouldn't be surprised to see something emerge soon though.

[1] http://en.wikipedia.org/wiki/Assisted_GPS

[2] One example: http://ws2.binghamton.edu/fowler/Improving%20WLAN-Based%20In...

Re: The Hack That Brought Foursquare Back From The Dead

#24
post #23

Earlier quoted context omitted.

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…

The primary purpose of WiFi to enhance location information is to bootstrap the download of current GPS orbits (the ephemeris) [1]. More advanced techniques relying on radio signal strengths, RTT time, and other observables [2] are being developed but I don't know of any in widespread use. I wouldn't be surprised to see something emerge soon though. [1] http://en.wikipedia.org/wiki/Assisted_GPS [2] One example: http:…

Skyhook absolutely relies on radio signal strengths and other observables and so do Google's location services.

This can be observed in practice as Android tablets and Apple devices with no GPS or cell radio at all can still locate themselves relatively well.

http://www.skyhookwireless.com/apps-enterprise/ has the marketing-bling diagram of Skyhook's use of multiple observables to determine location; even as of 4 or so years ago when I last used their API you sent them MAC + RSS and got back location.

Re: The Hack That Brought Foursquare Back From The Dead

#25

foursquare is still around? Hyperbole aside, I thought foursquare was an excellent idea - and if more businesses around me used it, I"d probably still be using it myself. (Reading the article, it seems that if you live in NYC or SF it's a lot more useful than it's been to me.) As it is, I think the last time I even looked at it was nearly six months ago.

this is basically spot on regarding my use as well... where I live, foursquare is marginally useful, but when I travel to NYC/ SF/ DC it is usually one of the first apps I open and I find it pretty valuable.

Re: The Hack That Brought Foursquare Back From The Dead

#26
post #23

Earlier quoted context omitted.

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…

The primary purpose of WiFi to enhance location information is to bootstrap the download of current GPS orbits (the ephemeris) [1]. More advanced techniques relying on radio signal strengths, RTT time, and other observables [2] are being developed but I don't know of any in widespread use. I wouldn't be surprised to see something emerge soon though. [1] http://en.wikipedia.org/wiki/Assisted_GPS [2] One example: http:…

Google actually does collect wifi location data via Android devices. There's a setting that allows you to toggle this data on/off. If you turn it off, it actually disables the course location API available to Android apps (I recently encountered errors with both the Lux and the UCCW Android applications due to the fact that I had this setting disabled and those apps only had course-location built-in).

Now whether Android actually uses the wifi data to determine location, as opposed to simply collecting it and manually disabling course-location if you don't send them wifi data, I have no idea. It does seem to be related though to the new Geofencing API available in the latest versions of Android.

EDIT: Sources!

http://www.zdnet.com/blog/networking/how-google-and-everyone...

http://developer.android.com/training/location/geofencing.ht...

Re: The Hack That Brought Foursquare Back From The Dead

#27

> Foursquare already had a massive database of check-ins — location information about the places its users most liked to go. And this data didn’t just include the place where someone had checked in. 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. Leveraging this data meant that Foursquare could still grab a good…

>> 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.

Re: The Hack That Brought Foursquare Back From The Dead

#29
post #23

Earlier quoted context omitted.

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…

The primary purpose of WiFi to enhance location information is to bootstrap the download of current GPS orbits (the ephemeris) [1]. More advanced techniques relying on radio signal strengths, RTT time, and other observables [2] are being developed but I don't know of any in widespread use. I wouldn't be surprised to see something emerge soon though. [1] http://en.wikipedia.org/wiki/Assisted_GPS [2] One example: http:…

Indoor positioning methods are being developed, outdoor methods are in use for years now. It's how positioning works on your laptop, e.g. in Google Maps.

http://en.wikipedia.org/wiki/Wi-Fi_positioning_system

"Commercial providers of this type of positioning service include Google,[1] Navizon, AlterGeo[2] and Skyhook Wireless."

Re: The Hack That Brought Foursquare Back From The Dead

#30
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.

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.
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