Location is one of my hobbies. Even though I don't map items for openstreetmap and the like, I still try out at least every location-related startup there is.
Foursquare, as you probably know is a location-based game — get points and badges to check into locations. The points are aggregated into weekly leaderboard (of penis envy) and everyone gets a fresh start every Monday morning.
Foursquare has different check-in modes. One is the regular, where your location gets published to your friends (and also Twitter/Facebook if those are linked up) and the other is called "off the grid" — supposedly not even your friends know where you're at.
Think of a possible scenario — cheating on your diet? You can still check into McDonald's and get the points but your boyfriend wouldn't know you did it.
Is off the grid really off the grid? Far from it.
If you play Foursquare on a more national or global scale (e.g. between cities) even though you check in off the grid, your general location is updated on your profile.
So let's say I went from Berlin to Munich and didn't want anyone else to know. I still check in off the grid at the airport in Munich (to get a stupid badge or whatever) and my Foursquare profile would not show where I exactly I checked in (e.g. airport), but it would say "Till (Munich)".
From what I noticed the other week, if you checked into a venue and did off the grid, it would still show your icon on the venue's page on Foursquare, which doesn't really sound like advertised either.
So how is that check-in actually private? Well, not at all.
Location without a check-in
But wait, it gets even better!
I noticed that Foursquare's Android and Blackberry applications update your location without checking-in. From what I gathered, it's plenty to look at your friend list and sure as hell enough to scan for places around you (to get caught ;-)).
The friend list always shows people from the city you're in. So as soon as you open the application, it displays those. Whenever you leave the city, it'll say something like, "Friends in other cities" — and "Viola!", your profile got updated.
All of this is powered by the GPS tracking in your nifty phone. Pretty cool, eh?
Last weekend I went to Chemnitz to attend a family thing — even though didn't check in anywhere, I briefly scanned to see who and what was around me. Still, my profile got updated.
The above shows two check-ins, Jet is in Berlin (gas station) and Aral is near Dresden (another gas station — but don't worry, I just bought a magazine and took my dog for a walk — didn't need to fuel up).
And here's a shot of my profile, which clearly states I'm in Chemnitz:
I guess I should have expected it, but I'm still not sure if I like it. The upside is, it's pretty accurate too (note, sarcasm)!
And in case anyone got doubts — I'm sure someone with elite jedi powers from Foursquare can verify that I didn't cheat.
I think the biggest mis-conception here is that I expected Foursquare to share my location only when I do something using the application or the website. I'd really like it to be a more active thing when my profile is populated with data. On the other hand, that's probably inconvenient as hell for … Foursquare?
I haven't really checked into this any further, but does anyone know if the Foursquare applications use background data?
I would like to how much of my location is shared on a regular basis and also how granular the data gathered is, e.g. Foursquare only updates the city/country on your profile, but do they really keep latitude and longitude?
Not the usual programming bs. :-) And that's all for today.
If in doubt about your data, you should disable location based services.
The very least you can do is to learn enough about them in order to understand (and comprehend) what's happening with your data.