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Police Using Apple iOS Tracking Data For Forensics 208

Posted by Soulskill
from the i-know-what-you-did-last-summer dept.
Several readers have sent in follow-up articles to Wednesday's news that iPhone location data was being tracked and stored. First, it seems Android shares a similar problem, though the file containing the location data is "only accessible on devices that have been rooted and opened up to installation of unsigned apps." Developer Magnus Eriksson has created an app to flush this data. Next: the iPhone tracking file is not new, just in a different place than it used to be. Reader overThruster then points out a CNet story indicating that law enforcement has been aware of this file for some time, and has used it in a forensics context. This story is a growing concern for Apple, particularly now that Senator Al Franken (PDF) and Rep. Ed Markey (PDF) have both written letters to Steve Jobs demanding details about the location tracking. Finally, PCMag explains how to view the location data present on your iPhone, should you so desire.
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Police Using Apple iOS Tracking Data For Forensics

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  • by tripleevenfall (1990004) on Friday April 22, 2011 @03:59PM (#35909960)

    Some blogger told us yesterday there was no reason to panic, and this data was perfectly safe.

    • by couchslug (175151)

      My Reality Distortion Field will prevent anyone from reading my information.

    • Re:Whoa, whoa. (Score:4, Interesting)

      by plover (150551) * on Friday April 22, 2011 @04:22PM (#35910164) Homepage Journal

      Your phone's location data has always been available to anyone who presents a warrant to your phone company. This just makes it easier to perform warrantless searches like they do in Michigan.

      Anyone with a cell phone should have an understanding of this. If you bring a cell phone with you while you're committing a crime, don't be surprised if it's used as evidence against you. And if you bring a cell phone to Michigan, learn how to say NO to the cop who asks you if he can see it. At least in America, you are still not required to cooperate in investigation against you.

      • Re:Whoa, whoa. (Score:5, Interesting)

        by Lord Byron II (671689) on Friday April 22, 2011 @04:33PM (#35910262)

        Well, keep in mind that there is a difference between being asked and being told to do something. If a cop asks you:

        "Can I see your cellphone?"

        Then, you're under no obligation to answer in the affirmative. However, if he says:

        "Hand over your cellphone."

        That's a demand and you're legally required (with some exceptions) to comply. Although cops are well-trained and they know how to phrase a question such that it sounds like a demand:

        "I'm going to take a look at your cellphone. Would you hand it to me?"

        The point is that when talking to the police, stay calm and listen to exactly what they're saying. If you're not clear if something is a question or a demand, then ask for clarification.

        • Re:Whoa, whoa. (Score:5, Insightful)

          by causality (777677) on Friday April 22, 2011 @05:49PM (#35910972)

          Well, keep in mind that there is a difference between being asked and being told to do something. If a cop asks you:

          "Can I see your cellphone?"

          Then, you're under no obligation to answer in the affirmative. However, if he says:

          "Hand over your cellphone."

          That's a demand and you're legally required (with some exceptions) to comply. Although cops are well-trained and they know how to phrase a question such that it sounds like a demand:

          "I'm going to take a look at your cellphone. Would you hand it to me?"

          The point is that when talking to the police, stay calm and listen to exactly what they're saying. If you're not clear if something is a question or a demand, then ask for clarification.

          I can talk to elderly people who remember a time when cops were not state-sponsored thugs who rigorously searched for every possible way to nail you with something. Seriously... what kind of psychotic assholes thought it would be a great idea to train cops to request optional cooperation in a manner that sounds like a mandatory demand? What kind of world do people like this hope to live in?

          Even if I were the undisputed dictator for life, an autocrat with absolute power, a sovereign whose orders are always obeyed without question and without hestiation, a ruler without rival, the man in charge of everything ... I still would not want to live in a dictatorial police state. I still don't want to be surrounded by that kind of misery and disharmony. I especially wouldn't want to be even partially responsible for it. No affirmation of my ego would be enough to make it worthwhile.

          In some ways I can easily understand the minds and spirits of power-hungry people. In some ways I can easily grasp why the USA is becoming a police state. I see the forces at work driving both. They're the same type of perversion and corruption that has befallen every great nation. It's what possessed every bloodthirsty mass-murdering tyrant throughout history, and by that I refer to those who had motives other than self-defense. The history books usually refer to them as "conquerors" with a certain awe. As the saying goes, if you kill a man you're a murderer; kill many and you're a conqueror.

          But in other ways, I really don't understand it at all. I mostly want to be left alone to live my life as I see fit. Taking responsibility for my life, not allowing my decisions to harm others, and respecting the freedom of others to live as they see fit are the only obligations I truly recognize. Yet for those who view life as one gigantic struggle for control of others, it's just a matter of who's holding the reins. Each would like to be that person or a member of that group. Often, this is even portrayed as normal and is rarely questioned. As common as it is, as predictable as its machinations are, this mentality is completely alien to me. I know it only through outside observation. Am I in a small minority here? Am I really?

          If so, cops who find petty deception and intimidation useful, not so they can solve some heinous crime and bring a dangerous criminal to justice, but so they can brag to their buddies about how many additional charges they added to some poor schmuck who was a threat to no one ... well that's just the beginning. They think they're running the show because they can push civilians around? They're dogs on a leash to the truly powerful, obedient and loyal so long as their "appetites" are satisfied.

          What a shame. We could have a much more beautiful world than this.

          • Re:Whoa, whoa. (Score:5, Insightful)

            by plover (150551) * on Friday April 22, 2011 @06:41PM (#35911326) Homepage Journal

            It starts out as simple corruption. Like most jobs, cops are reviewed on how much output they produce. Yes, they may have found ticket quotas to be unconstitutional, but there is an understanding that if Officer Jones brings in 5 guys with 3 charges each, and Officer Smith brings in 5 guys with 1 charge each, guess who gets promoted to Lieutenant? Hint: it's Jones.

            And they're not stupid. They're trained on techniques that bring in more bad guys. If Officer Jones really wants that Lieutenant rank, he's going to use them. They also don't have to be reasonable, because they can always leave it up to the judge to determine reasonableness. As long as they follow the rules to the letter, if they want to try things like warrantless searches just to boost their own image in the eyes of their boss, they will.

            The thing is that many people don't view that as corruption. "He's a go-getter!" "He makes things happen!" Those are compliments. And if a cop uses a warrantless search and uncovers a guy who phoned a drug dealer, then uses that as probable cause to search for and find a joint in his car, politicians will celebrate a victory for the system -- never mind that the search was a fishing expedition launched for selfish corrupt reasons, and that they're prosecuting a guy for a victimless "crime". "He made things happen!" And if the dirt that led to the arrest is ever exposed, the politicians decry it as a "liberal judge legislating from the bench."

            It's a corrupt system, yet for the most part it's still better than all the alternatives history has demonstrated.

        • by ljw1004 (764174)

          "I'm going to take a look at your cellphone. Would you hand it to me?"

          I can't tell whether that's a question or a demand, even after you told me.

        • The proper canned response to every law enforcement request should be, "My lawyer has advised me not to make any statements without first consulting him." No matter how they phrase their request and no matter how intimidating or benign they may seem, those should be the only words to pass your lips, which should be the only muscles you use during your encounter. If they say they have a right to search something, it can only be done with a warrant, and if they say they have a warrant, ask to see and review

        • by Nyder (754090)

          Well, keep in mind that there is a difference between being asked and being told to do something. If a cop asks you:

          "Can I see your cellphone?"

          Then, you're under no obligation to answer in the affirmative. However, if he says:

          "Hand over your cellphone."

          That's a demand and you're legally required (with some exceptions) to comply. Although cops are well-trained and they know how to phrase a question such that it sounds like a demand:

          "I'm going to take a look at your cellphone. Would you hand it to me?"

          The point is that when talking to the police, stay calm and listen to exactly what they're saying. If you're not clear if something is a question or a demand, then ask for clarification.

          I suggest you say No to any of there questions. If they start getting pissed, ask if you are under arrest. When they say no, then tell them you are leaving.

          If they say yes, then don't say anything at all. Get a lawyer and have him/her handle it.

          And the cops will try to make you seem like your a criminal and they will lie to you, because it's part of their training.

          Never, ever cooperate with the police, because it will be used against you.

        • then hand it to them.

          Nothing requires it work.

      • by rsborg (111459)

        [...] At least in America, you are still not required to cooperate in investigation against you.

        I'm less worried about short-circuiting my criminal defense, and more worried about plain old corruption. This puts a LOT of power into police hands, they could go on a fishing expedition at will.. especially with those devices that pull out data in 2 or 3 minutes, that's plenty fast enough for a police stop.

    • Well, since the data is stored on your device which is presumable under your control, and it isn't sent anywhere, and it server a functional purpose as part of the A in A-GPS, I'd say your blogger was correct.
  • Not so similar (Score:5, Informative)

    by loconet (415875) on Friday April 22, 2011 @03:59PM (#35909964) Homepage

    Worth mentioning in Android's case is only used for caching so the data gets overwritten every so often. Unlike iPhone's

    • Re:Not so similar (Score:5, Interesting)

      by Anonymous Coward on Friday April 22, 2011 @04:42PM (#35910356)

      Then why can I type in the BSSID (MAC address) of my WiFi router into http://samy.pl/androidmap/ and via google it will tell me exactly where it is?

      Every time my Android phone connects to my router at home it uses 3G data just before doing so. Whether or not the phone's recording the info locally, it sure is sending it to Google.

      If if was just kept locally that'd be one thing, but it's going much further and telling a third party the co-ords. That's much worse than what Apple's doing.

      • by Nerdfest (867930)
        I'm fairly sure that Google (via their Street View cars) and others companies have recorded the MAC address of every router they could pick up. This is what they were doing when they picked up the extra non-encrypted data everyone seems to be up in arms about.
      • by cforciea (1926392)
        We have a broadcasting SSID here that has been active for ~4 months. We have employees with android phones. Our wireless MAC is not in that database. Something here is fishy.
      • by jeaton (44965)

        Apple does WiFi location as well. That's how the WiFi-only iPad and iPod touches can get location data.

        Skyhook and other similar services provide WiFi access point MAC/SSID to location mapping services. They have people (essentially) war-drive, scanning for WiFi networks and record the locations based on GPS units and upload that to a database. Then, when you have a device which uses their service, it can query the database and get back the previously cached location.

        This is, in part, why my iPhone kept loc

    • Worth mentioning in Android's case is only used for caching so the data gets overwritten every so often. Unlike iPhone's

      When you say "overwritten" does the same transistor array get rewritten or is the operation subject to the wear leveling algorithm like everything else on the file system meaning the data can still actually be recovered leaving it in reality no better than the iphone?

      • I'm sure even my cheap dumb phone has stored my DNA too.
      • by Rennt (582550)
        A temporary cache that might be partially recoverable using advanced forensics under ideal contitions is "in reality no better" then a permanent .db file that can be simply copied off the device? The RDF is strong with this one.
    • by Anonymous Coward

      Both are caches, one is bigger than the other. Also, they fail to mention that the file on the iPhone is also not accessible unless the phone is jail-broken (or rooted). People are choosing the words they want to use to make one look worse than the other.

      I used to come here for intelligent comments, not having to provide them.

    • by msauve (701917) on Friday April 22, 2011 @04:49PM (#35910434)
      Google explains what they're doing, and offers the user a choice. When turning on Google Location Services on an Android phone, you get this message:

      Location consent
      Allow Google's location service to
      collect anonymous location data.
      Collection will occur even when no
      applications are running.


      Agree Disagree

      OTOH, it's reported that Apple's location collection cannot be disabled, even if you turn off "Location Services."

      According to the original article about the iPhone file, the location info appears to be based off cell tower triangulation.

      What Google is doing with is mapping the location of WiFi access points. If you have GPS and Google Location Services on, when an AP is seen, it will tell Google the MAC address of the AP, and the geographic coordinates from GPS. This is what lets location services work even without GPS - when your phone sees a WiFi signal, it will ask the mothership where it's located. So, with Android, the user is providing info which in turn helps other users, and it's all being done with knowledge and consent.

      Phones can do something similar based on the cell towers they see, but geographic info on those is available from the FCC and the carriers, so Android doesn't have to collect info on them.

      So, Google is using a phone's location to map the location of WiFi APs, while Apple is using cell tower locations to record the phone's position. Those are two very different things.

    • Actually, the iPhone file is a caching file. It retains one entry per cell tower to which it's been connected and overwrites that entry with updated location data (of the tower, not the triangulated location of the user) each time that tower is encountered. So, tracking the user is actually difficult within areas they commonly visit since only fresh data will exist. For places visited only once, that data may live in the cache much longer.
    • Worth mentioning in Android's case is only used for caching so the data gets overwritten every so often. Unlike iPhone's

      Well, accessing it every time an app run should be enough to get a nice movement profile about you anyway, all without the need to ask you if you want that. But it can only be accessed when you got root access, right? http://www.springerlink.com/content/d275570090ng72jt/ [springerlink.com]

  • Android (Score:4, Informative)

    by recoiledsnake (879048) on Friday April 22, 2011 @04:01PM (#35909974)

    First, it seems Android shares a similar problem, though the file containing the location data is "only accessible on devices that have been rooted and opened up to installation of unsigned apps

    Doesn't Android just store the past few days information unlike years together like the iPhone?

    • by plover (150551) *

      First, it seems Android shares a similar problem, though the file containing the location data is "only accessible on devices that have been rooted and opened up to installation of unsigned apps

      Doesn't Android just store the past few days information unlike years together like the iPhone?

      So it's degrees of evil? Do you really think the cops will "bust you less" if they only have a few days worth of your data?

      • by jhoegl (638955)
        You aint guilty unless you do somethin.
      • So it's degrees of evil? Do you really think the cops will "bust you less" if they only have a few days worth of your data?

        That would depend on the time period they were investigating, now wouldn't it?

    • Re:Android (Score:4, Interesting)

      by Sparks23 (412116) on Friday April 22, 2011 @04:57PM (#35910480)

      No, Android stores the last 50 unique cell-derived locations (in cache.cell) and the last 200 unique wifi-derived locations (in cache.wifi). In other words, the file /is/ truncated, but based on quantity of data rather than age/time. Apple's logfile is not truncated, whether by design or programming error.

      Conversely, Apple's log remains on the device only for Core Location caching; it's stored in iPhone backups, but isn't ever sent back to the mothership (at least so far as anyone has been able to tell). Google truncates the log, but does send the data when you hit a WiFi point and have a GPS signal; they use this to update their WiFi location database for GPS assist, as they use their own service rather than Skyhook. (If your base station advertises itself, open or otherwise, go to http://samy.pl/androidmap/ [samy.pl] and enter your local router's MAC address; you can see where Google thinks that base station is, based on how Android devices have paired your station to their GPS data.)

      • by Drakino (10965)

        This particular file isn't sent back to Apple, since all it contains is data provided from Apple already.

        The reason the cache exists was explained at WWDC 2010 (and possibly before). Keep in mind that not all iOS devices are cell phones, and some lack 3G data entirely, along with GPS chips. If you have Location Services turned on with an iPod Touch, and do searches in Maps, Apple sends down WiFi location data as part of the request to populate the cache. The idea is that even though an iPod touch lacks a

      • by _xeno_ (155264)

        Your location most certainly is sent back to Apple. It's in the iOS 4 license and also Apple's privacy policy [apple.com]:

        We may collect information such as occupation, language, zip code, area code, unique device identifier, location, and the time zone where an Apple product is used so that we can better understand customer behavior and improve our products, services, and advertising.

        Emphasis mine.

        Part of the reason for Apple to use this data is to build a similar database to Skyhook/Google's - but their privacy policy flat-out tells you that they also keep if for advertising, and that it's identifiable by time and device.

  • by v1 (525388) on Friday April 22, 2011 @04:01PM (#35909976) Homepage Journal

    between the cops' ability to subpoena cell phone tower records and this? just a bit more precision? they've been keeping track of this for decades

    • by bill_mcgonigle (4333) * on Friday April 22, 2011 @04:06PM (#35910020) Homepage Journal

      between the cops' ability to subpoena cell phone tower records and this? just a bit more precision? they've been keeping track of this for decades

      No subpoena required. Did you see the article here a few days ago about Michigan sucking all the data off of phones during routine traffic stops?

      Sure, it's patently illegal under the 4th Amendment to the US Constitution, but then again so are suspicionless checkpoints and yet we have Michigan v. Sitz.

      Michigan again - no wonder everybody is moving out.

      • Re: (Score:2, Interesting)

        by cosm (1072588)
        Unrelated to GPS tracking, I've heard people refer to Dearborn as Dearbornistan because things have gotten so bad in some areas. Its like the racial and ethnic barriers are being resurrected right back up, shame folks can't get past skin color, ethnicity, and religion. Some things never change.
      • by Fnord666 (889225)

        No subpoena required. Did you see the article here a few days ago about Michigan sucking all the data off of phones during routine traffic stops?

        Sorry I must have missed it. I did see what must have been a related article though about how Michigan police have a forensic tool that can make a copy of a cellphone's memory in a short amount of time. The same article mentioned a lawsuit/FOIA suit seeking usage data for the device. Nowhere in the article did it say that police had been observed doing this or that there was any evidence that any such thing had actually happened.

        • Nowhere in the article did it say that police had been observed doing this or that there was any evidence that any such thing had actually happened.

          You're right, it's not certain that Michigan police have been using that particular device. They may not be hiding anything at all with their half-million dollar FOIA fee request.

          We do know [yahoo.com], however, that police are using that data, through some means, to investigate and convict.

  • by sanchom (1681398) on Friday April 22, 2011 @04:01PM (#35909980)
    Also, it's not as cool as first reported... it doesn't actually track your every move: http://sanchom.wordpress.com/2011/04/21/your-iphone-isnt-following-your-every-move/ [wordpress.com] I wanted to see the paths that I followed around North America San Francisco, Winnipeg, Montreal, Vancouver, Seattle, and lots more of Vancouver. I was disappointed. I rarely saw a little stream of location markers showing “my every move”. I looked closer at the data, and it seemed very sporadic. Sometimes days would go by without a timestamped location. Other times, like when I was using Latitude to update my location during a bus trip from Vancouver to Winnipeg, updates happened much more often, sometimes multiple times per minute.
  • by cosm (1072588)
    This does not come as unexpected to me in the age of the Police State. Nothing to see here folks, move along. It will be interesting to see how the congresscircus handles this, if they try to skewer Apple like they did Google, along with the other countries that hemmed and hawed over Google data. You've got the apologists saying "oh, well, its not that bad", but in reality the more we become desensitized to location tracking, the worse it will get. How many years in the future until somebody discovers thei
    • Ooohhhh... where can I get these GPS shoes?
      • by cosm (1072588)
        Not sure if your being sarcastic or missed the hypothetical, insert any [x] mundane take for granted object and I imagine its a matter of time before a large majority of things are tracked at the current rate of growth. Either that or you whooshed me with your intended jesting.
        • Just being silly.
        • Additionally, it's not just GPS. RFID is actually almost as sinister. They're cheap, require no stored power source, and could conceivably be inserted into everything you own. While you couldn't be tracked (easily) out in the country, any business or government office you walk into could have an RFID sensor making it possible for you to leave breadcrumbs all over the place.
    • This has nothing to do with a 'police state'. It has everything to do with companies getting more and more data about so they can 'improve' their marketing.

      Its all about trying to sell you more products, nothing more. That the police can use it too is just collateral damage.

  • All cell-phone manufacturers are required to have GPS data for emergency 911 response. This is required by US law. It seems disingenuous that politicians are now upset that this data is being recorded.
    • I thought it was cell network operators that are required to have that data, not phones.

      Even if phones do require it, they most certainly don't require logging it. I can understand caching, say, the last few minutes, maybe a few hours at most - just so that cached information can be quickly transmitted if there's no other data. But iPhone logs that stuff for months.

    • All cell-phone manufacturers are required to have GPS data for emergency 911 response. This is required by US law.

      Huh? Where do people pull this stuff from? It's possible you're just confused, but the way you phrase that resembles a deliberate misrepresentation more than an honest mistake.

      I believe by law the cellular service provider is required to send any available location information to 911 at the time a call to 911 is made. This means that information about the cell tower the phone is currently using will be sent, along with any coarse triangulation data, and, if the phone has a GPS, the GPS will be activated and

      • I did a bit of research, and it looks like in 2005 a law went into effect in the U.S. that requires a service provider to be able to locate a subscriber within 100 meters when they dial 911. A GPS is not required for this because it can often be obtained using triangulation, but it looks like most providers of even cheap phones started included them anyway.

        So no, the law does not require a GPS in every cellular phone. However, it looks like it may have had the same effect.

      • by tombeard (126886)

        So,does anyone know how this is turned on? I imagine a properly coded sms?

    • All cell-phone manufacturers are required to have GPS data for emergency 911 response. This is required by US law. It seems disingenuous that politicians are now upset that this data is being recorded

      There is no requirement any location data be stored in non-vilotile memory for mobile e911 system to function properly...

      To put it another way...your cell phone keeps records of your SMS sessions. It is disingenuous that you would now be upset that this data is being posted in the front page of the new york times.

  • Apple had acknowledged to Congress last year only that "cell tower and Wi-Fi access point information" is "intermittently" collected and "transmitted to Apple" every 12 hours.

    I seem to remember dozens of people saying "It's just on your phone, it's not like Apple is collecting the data" in the previous thread about this.

    Yet Apple has even said they are collecting it.

    I don't mind anyone being a fainboi, just be honest about it.

    • Apple had acknowledged to Congress last year only that "cell tower and Wi-Fi access point information" is "intermittently" collected and "transmitted to Apple" every 12 hours.

      Citation? I don't doubt you, but just because you type it does not make it true. Especially in the auspices of someone who decries fanboi-ism, I'd expect to see an avoision of even the appearance of impropriety in fact-reporting.

  • It seems Android shares a similar problem, though the file containing the location data is "only accessible on devices that have been rooted and opened up to installation of unsigned apps."

    It's the same with Apple, you either need to jailbreak to access the file (since regular apps can't access that space), or pore through your backup from iTunes.

    I don't care about this, I don't give people access to my phone, and I'm sure AT&T already has the identical location data, since the file only showed very broad cell tower data, like the fact that I'm in the east side of a city but that's it. The government would only have to look at my credit card records to find out where I was.

  • by bhcompy (1877290) on Friday April 22, 2011 @04:29PM (#35910240)
    OnStar records all driver information as well, and has been used in court against drivers. The FBI has also used it to track/bug people.
  • printer [wikipedia.org] tracking was taking place for a decade before being made public by EFF [eff.org]
  • by bugi (8479)

    So in other words, black hat law enforcement hackers have known about the vulnerability and have been exploiting it for some time?

    Given that law enforcement is by and large a State actor with the requisite influence, are we sure these aren't purposeful back doors?

  • "This story is a growing concern for Apple, particularly now that Senator Al Franken (PDF) and Rep. Ed Markey (PDF) have both written letters to Steve Jobs demanding details about the location tracking."

    These senators are even STUPIDER than I thought. Congress mandated this kind of stuff in the Telecommunications Act of 1996! Who the hell are they kidding! They OBVIOUSLY didn't read the law they passed - not unusual for are brain dead congress people!

  • Usual Apple spin (Score:2, Insightful)

    by bcmm (768152)

    So here we are again, hearing "everybody else is as bad". Anyone else reminded of how everybody else's phones can be held wrong too?

    Caching the data for a matter of days is not the same as saving it forever and copying it to other devices, just as being an ordinarily radioopaque human is not the same as poking the actual antenna.

    • by _xeno_ (155264)

      Not to mention that thanks to a letter Apple wrote last year, we know this data is being sent to Apple [wired.com].

      Before it was unknown if Apple was actually tracking users, but apparently hidden in the iOS 4 TOS was the fact that Apple will upload your GPS coordinates and nearby wi-fi networks in order to avoid having to license Skyhook's geolocation database. It's easily found in their privacy policy [apple.com]:

      To provide location-based services on Apple products, Apple and our partners and licensees may collect, use, and share precise location data, including the real-time geographic location of your Apple computer or device.

      Needless to say this only applies to iOS devices with GPS chips - but then again, Apple already knows your location a

  • The file [on Android] is only accessible on devices that have been rooted and opened up to installation of unsigned apps.

    Then what is the purpose of this file? There has to be some app or something that motivates collecting this data in the first place...

    • by drb226 (1938360)
      Also, what about Cyanogenmod, or other Android mods? Do they keep this file around? Why/why not?
  • If all the smart phones seem to be snooping on their owners, then perhaps it's time to go luddite.

    Note to Apple & AT&T: my contract is up in June. Please have this fixed by then, or else.

  • by NotQuiteReal (608241) on Friday April 22, 2011 @10:18PM (#35912418) Journal
    Statistically speaking, nobody cares where you have been.

    But there is a reason to see if somebody was in a particular place. I wonder if there is a mechanism for law enforcement to do a "reverse" search for "who was at this location" (rather than where has "user x" been).

    This technology would be a great way to start looking for suspects. E.g. "a body was found in the ravine..." So search all cell records with approx locations near the ravine during the time of interest.

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