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Comment by watty | Hacker News Reader

http://netmite.com/android/mydroid/frameworks/base/location/...

It appears that unlike Apple, this isn't unlimited:

    // Cache sizes
    private static final int MAX_CELL_RECORDS = 50;
    private static final int MAX_WIFI_RECORDS = 200;

Edit: Seems like another very important difference is that the Android cache only keeps track of your last timestamp at a given tower. Even if this cache was unlimited it couldn't be used to plot someones position over time.

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> Seems like another very important difference is that the Android cache only keeps track of your last timestamp at a given tower.

This is true of the iPhone cache as well. See http://news.ycombinator.com/item?id=2467895

You may be right but this user seemed to plot a graph with "most often" visited places: http://www.southbayriders.com/forums/showthread.php?t=108489...

The unlimited size of Apple's cache is probably just a mistake. It makes no sense to store it on the device for tracking purposes. I assume they log this info when the device requests the info from Skyhook (or whatever location provider they have now) anyway.

I can confirm that the Android cache.cell and cache.wifi lists are very limited. I just checked mine using your parse.py, and was only able to see 50/200 total records respectively. My cell data only went as far back as 13 days ago.

"The unlimited size of Apple's cache is probably just a mistake."

I think this is what concerns people most. This "mistake" has your triangulated location based on cell towers tracked for years and years, across multiple devices, when there really is no recognizable need to store/cache this much location data for this long. It seems, judging by the above linked source-code, that Android has it right on this one.

I ran the program and looked at my iPhone dump, and it is not that exact and I live in NYC. It truly appears to just tag position of towers. Where it shows the dots for me is not exact or even close positions most of the time, and even locations that I've never been to but the nearest tower I must've connected to.

Which is helpful for me since I've long suspected AT&T has a dearth of towers in my section of the UES, maybe I can get a microcell out of this, haha.

I'm guessing you knew that Android has a cache that rolls over prior to posting - were you just trying to stir up discussion/controversy with the misleading headline?

I did. The title wasn't meant to mislead though. More of a tongue-in-cheek remark. Hence having "tracks" in quotes. Personally I think the whole "OMG APPLE TRACKS US!!" thing going on is overblown.

Looking at it now I guess it can be seen as misleading. It wasn't my intention though.

edit: changed the title ..

     "OMG APPLE TRACKS US!!" thing going on is overblown

It isn't -- consumers should be aware that these services represent a net loss for their privacy on the long term.

If a device tells you that it is tracking you; eventually giving you the possibility of opting out, deleting all tracks of you on request, then it's fine by me. But otherwise it isn't, and this practice should really stop.

And here I was a couple of months ago, thinking about how cool / evil would be to make an app that tracks someone's route for spying purposes (like your girlfriend for example). Apparently iPhones give it away for free, no extra work required ;-)

Wow.. I didn't even think of this angle. Think of how many jealous boyfriend/girlfriends there are with complete access to their mate's iphone. :/

Not only jealous boyfriends -- give your employees iPhones, and they'll surely synchronize it at least once a month on your company's computers ;)

Phones with GPS incorporated can be mindbogglingly evil -- just think about the costs involved in hiring a private eye to track the daily route of someone, day after day, for a whole month. People don't do it because of the costs involved and because an incompetent can blow away his cover.

iPhones are equipped with GPS, and that data is there, waiting for you to retrieve it. You don't have to do anything special about it -- you just have to gain access to that iPhone somehow.

I'm not accusing Apple of anything, I really think it was just a minor slip-up on their part. But these things are dangerous ;)

Except, if the employee never uses any location services on the phone, none of the data is ever created/stored in the first place ... at that point you still have gained nothing.

The only records I have for example are from when I explicitly had Google Maps open, no other program on my iPhone has my permission to use the location based services, and as such it didn't track where I was going at all.

That's not really true... the iphone tracking happens regardless of location settings or applications.

The location controls do not affect it at all.

The latest entry in any of the tables on my phone (and I've been out of my usual locations for a while now) (CellLocation, WifiLocation) are from almost 4 days ago, which is the last time that I used Google Maps to get directions to chines buffet I was meeting a co-worker at.

If this was being tracked even when using non-location services wouldn't that be updated every time I pass by a new cell tower? Wouldn't it know about the trip I made with a co-worker to a town I've never been to before?

Can you point me where in the tables there is data (based on timestamps) that is updated more often and kept around?

You don't necessarily even need their phone, you could use your own phone as the tracking device and have the person willingly, but unwittingly deliver the data. Just "forget" your phone in their car before you suspect something and after a the suspected event, ask for it to be returned.

Knowing you've been in Göteborg, Sweden recently is one thing (or at least that's what the test data says), but location history going back the device's lifetime is another.

It makes no sense to store it on the device for tracking purposes.

It would make sense to store this information on a server, so why aren't they? Is it a mistake, or are there laws that preclude this? Maybe it's track now, figure out what to do with it later. The data is extremely valuable.

Apple's consolidated.db is not a "mistake". A mistake would not have gotten rewritten for iOS 4 when the database got converted from XML to SQLite and moved to user data.

http://alexlevinson.wordpress.com/2011/04/21/3-major-issues-...

Also iOS no longer uses Skyhook as of iOS 3.2. Plus Skyhook is for Wifi access point location data, not cell-tower location data. Apple uses its own database for that now which you consent to update with your location data. http://www.f-secure.com/weblog/archives/00002145.html

> A mistake would not have gotten rewritten for iOS 4 when the database got converted from XML to SQLite and moved to user data.

If they are using CoreData as the storage engine, it is possible they changed backends without ever looking at what was stored in it.

Isn't it possible to plot someone's position over time, no matter what phone you have? I mean the carriers know which towers you've connected to and when, they have all the info you need to track someone, even across multiple phones.

sure, but physical access to someone's phone is a lot easier than being a carrier.

It appears that you can also delete it by doing a "Clear Data" for the location service in Settings application list.

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