Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
×
Privacy Your Rights Online

Ask Slashdot: How To Stay Ahead of Phone Tracking ? 259

An anonymous reader writes "In the last few years there has been a significant upsurge in subverting the cellular network for law enforcement purposes. Besides old school tapping, phones are have become the ideal informant: they can report a fairly accurate location and can be remotely turned into covert listening devices. This is often done without a warrant. How can I default the RF transmitter to off, be notified when the network is paging my IMSI and manually re-enable it (or not) if I opt to acknowledge the incoming call or SMS? How do I prevent GPS data from ever being gathered or sent ?"
This discussion has been archived. No new comments can be posted.

Ask Slashdot: How To Stay Ahead of Phone Tracking ?

Comments Filter:
  • Don't carry one (Score:5, Informative)

    by siddesu ( 698447 ) on Monday April 01, 2013 @04:10AM (#43329043)
    As you know, they can track you even when the device is off, unless you've taken the battery out.
    • This may well be the case for some phones but I'm not convinced that it it is for all phones. Mind you I'm more than happy with my "dumb" phone and have no interest or use for a "smart" phone - who the fuck knows what they are sending out, off or on.
      • Re:Don't carry one (Score:4, Insightful)

        by gomiam ( 587421 ) on Monday April 01, 2013 @05:21AM (#43329241)
        Not to raise your paranoia, but your "dumb" phone isn't as dumb as you think it is. While it is acting as cell phone it needs to keep the towers appraised of its location so you can receive calls and it can roam from one cell to the next.
      • Re:Don't carry one (Score:5, Interesting)

        by FrkyD ( 545855 ) on Monday April 01, 2013 @05:37AM (#43329293)

        Well, we have known for quite some time that is is not just possible to use your dumb phone as a roving bug while it is turned off, but that it has actually been done.

        http://news.cnet.com/2100-1029-6140191.html [cnet.com]

        So even though you sound a bit (albeit justifiably) paranoid, you might not be paranoid enough.

        • Re: (Score:3, Interesting)

          by gl4ss ( 559668 )

          the article describes a technique in which the phone is NOT turned off but instead is hacked to _place a call_. that sounds suspect technique, actually, even if some razrs have hackable firmwares. you could keep it next to a radio to notice that something is up - and this would be an undertaking to essentially rewrite the entire firmware of the phone better than what motorola could - while retaining all the stock functionality. it sounds very, very james bond spy shit - bordering on being plausable as just

      • by equex ( 747231 )
        To disable the GSM module you have to enter a code on the dial. It does need a battery, obviously, so the only way is to take it out.
      • This may well be the case for some phones but I'm not convinced that it it is for all phones. Mind you I'm more than happy with my "dumb" phone and have no interest or use for a "smart" phone - who the fuck knows what they are sending out, off or on.

        'Smartphones' generally know more, by virtue of having a UI that makes doing lots of personally-identifiable stuff and storing lots of potentially sensitive data attractive; but if it's a cellphone, it has cellular communications capabilities, which are ample for at least lowish resolution tracking.

    • Re: (Score:2, Informative)

      by gl4ss ( 559668 )

      umm that's only the case if they've managed to fit something on your phone.
      on most any phone offline mode means no connection to network.. but if you want to be conected you're going to be paged all the fucking time for your info. so staying in offline mode is the answer. of course you can't know if someone is calling you or not.

      and if you're worreid about gsm attacks put your phone into umts only mode.

      • I have it. (Score:5, Funny)

        by BrokenHalo ( 565198 ) on Monday April 01, 2013 @05:56AM (#43329349)
        I am in a position to offer a perfect solution. Just move to rural Australia and move your phone contract to Telstra. They are so fucking incompetent, nobody will ever succeed in tracking you.

        The only downside is that you won't be able to make phone calls either. :-/
    • Re: (Score:2, Interesting)

      by Anonymous Coward

      i have taken apart a "donated" huawei ascend2 earlier this year and found small watch type batteries hard wired (soldered) on to the circuit board
      they were very small , 2 in quantity and were 3 volts each i dont know what they are used for other than to power the device even with the battery out
      its amazing how few chips were in this devithe whole board had like three or four chips a couple of speakers and a couple of mikes and the sdcards
      when i opened it i expected it to be jam packed full of components but

      • Re: (Score:3, Informative)

        by Anonymous Coward

        It's called a real-time clock. Your computer has one. A builtin battery too.

        • Comment removed based on user account deletion
          • Yeah, it would be awesome if your phone lost all settings every time it ran out of battery :)

        • by Overzeetop ( 214511 ) on Monday April 01, 2013 @06:27AM (#43329443) Journal

          That's what that battery is for - the mind control circuit. It's the only way they're keeping the people in line.

          What most people don't know is that *that* is why there's a battery in your computer too! It has nothing to do with the stupid clock. The clock doesn't need the battery! You've seen the ones that work with a potato - that's proof enough that a clock doesn't need a battery. No, they have the computers programmed to reset your clock and bios after a short timeout to make you THINK you need that for the clock. And all you weak-minded losers fell for it, and the mind control circuit just keeps you believing that you need that battery.

    • Re:Don't carry one (Score:5, Insightful)

      by vux984 ( 928602 ) on Monday April 01, 2013 @05:24AM (#43329249)

      As you know, they can track you even when the device is off, unless you've taken the battery out.

      I don't dispute it's possible that the phone while 'off' is simply in standby and pops on now and again to ping the network.

      But.. if so, why does my Galaxy S3 take 10+ seconds to 'boot up' after it's been turned off, and then another 5-10 seconds before it has service?

      There might be some phone out there that is 'always on'... but is there actually one? More than one? Is it actually common?

      This seems more 'urban ledgend' / paranoia then real -- the sort of paranoia where you think the NSA has installed a rootkit to simulate your phone shutdown sequence when you turn it off while it remains transmitting. Possible, theoretically? Sure.

      But then what makes you think taking the battery out will work? The NSA inserted a secondary battery with enough juice to keep tracking you for days even when the battery is out. Better put the phone into your pocket faraday cage...

      And take a shower and change your clothes to rinse off the micro RFID they hid in the dirt on your shoe and are tracking with a satellite equipped with some sort of super pringles antenna...

      I think my Galaxy S3 is off when I turn it off. I'm prepared to be educated that it really isn't, but I need more than some handwaving or links to rumors on some guys dubious blog.

      • Better put the phone into your pocket faraday cage...

        Great. Another ad for Aluma-Wallet. Didn't realize they had a giant one now, big enough to fit a common smartphone.

      • Re:Don't carry one (Score:5, Interesting)

        by hAckz0r ( 989977 ) on Monday April 01, 2013 @07:20AM (#43329713)

        I think my Galaxy S3 is off when I turn it off.

        That switch that you use to turn your phone off is nothing but a sensor switch. Its not a physical on/off switch disconnecting the battery from the phone circuits. When you press it, the OS on the phone is programmed to start shutting down certain circuits within the phone. It keeps other circuits powered up so that it can sense that same switch to bring the phone back up to its normal powered state.

        That being said, someone can reprogram the phone to 'look like' its powered off. It can still be recording audio/video to the local memory, or whatever it wants to, and even use the transmitter periodically without being noticed by the owner.

        The phone can be reprogrammed fairly easily by someone who gains control of the device. How easy is that? I've seen a demonstration by an expert that took all but 15 seconds to have root on a popular phone. All that was needed was an IP address of the data connection for the handset. In an instant they had the equivalent of ftp and could have done anything on that phone, including staging a boot loader/update waiting for the next time you cycled the phone's OS.

        For someone who has the power of the courts behind them, they can easily have the phone company push an update out to the phone to do the same thing. Nobody needs to hack your phone, and they can then completely control the outward appearance of the devise without you knowing anything about it.

        Other than having an RF monitor next to the phone you likely won't be able to detect it. A small RF monitor can be purchased and hacked to add a audible warning if the phone becomes active, if you are the tin foil hat type. Otherwise, if the phone is active and uses the network the battery will get slightly warm, even when turned off, so you might be able to tell that way. A cheap way to tell is a liquid crystal temperature strip adhered to the outside case where the battery compartment is. This is also a help if your phone has a battery drainage problem with certain apps, because it will tell you when the battery is being drained, and how quickly, for whatever reason.

      • by Thruen ( 753567 )
        Try setting your alarm and turning your phone off. My last maybe five phone have all had this functionality, probably before then too. Even your computer isn't really off when it's off, hell even after you unplug it it's not quite dead for days. If you've seen smaller GPS devices, things like pet trackers, you know they don't actually need the whole cell phone or a big battery to work. I'm not even convinced they can't track you AFTER you pull the battery. That said, it doesn't prove they're doing it. I hav
      • "This seems more 'urban ledgend' / paranoia then real..."

        I agree. Based on experience with my students in college classes, where the rule is that phones must be shut off (especially on exams), many if not a majority of people are confused about when a phone is really off versus when it is just in standby. I get a lot of students who claim a phone was off when it was ringing, or that they absolutely believe it's impossible to really shut the phone off. (Even in the face being penalized multiple times on a te

    • Buy a pay-as-you-go phone with cash, they can still track you, but they won't know who they are tracking.
      • Re:Don't carry one (Score:4, Informative)

        by DKlineburg ( 1074921 ) on Monday April 01, 2013 @05:35AM (#43329287)
        maybe not so? See article about your habits being unique and identifiable here on /.
      • Most of the cash prepaid phones still demand a name and address to activate. (YMMV... who are you using for burn phones these days?)

        • I think it depends on country. Some have regulations that make it very difficult (via liability) or outright illegal to provide a communications service without the ability to determine the identity of the user - predictably, usually introduced as a measure to fight the distribution of child pornography.

          • Good call on the jurisdiction dependent part of that.

            Honestly, I think they're more worried about (would-be) terrorists and drug dealers than CP, when it comes to phones...

            • Re:Don't carry one (Score:4, Interesting)

              by SuricouRaven ( 1897204 ) on Monday April 01, 2013 @09:20AM (#43330557)

              They did something like that with hotspots in the UK - the Digital Economy Act means that businesses can be liable for the infringements of people using their connection, which is a serious concern for all those places that used to provide customers with free wifi.

              In practice, some businesses have continued to recklessly provide the service, while many more have instead contracted with specialist companies who run the access point and authentication infrastructure on their behalf. Typicially it uses the mobile phone network as a way to validate identity: User connects, gets a captive portal, enters their phone number, the service provider sends them an SMS with the unlock code, user enters the code. It's somewhat cumbersome, and some people are understandably reluctant to give out their phone number, but it's the only way to provide customers with a convenience service (And thus lure them in, usually to buy food) without potentially getting sued for millions after someone goes on a torrenting spree.

              The only thing about the arrangement that surprised me is that the MPs were so open about the change in the law being about copyright. I'd have expected them to instead use child porn as an excuse, but they didn't: The Digital Economy Act is an entirely open effort to strengthen copyright law.

    • Yeah, dropping the battery is probably the best way to prevent it. But if you're an iPhone owner you're screwed. You can't easily drop the battery.

      That said, just put the phone in airplane mode. That shuts off all the radios including bluetooth, wifi and CDMA/GSM.
    • That's the safe way to be sure but many phones let you turn off the GSM transceiver with "airplane mode" or something like that.

  • turn it off (Score:4, Insightful)

    by thephydes ( 727739 ) on Monday April 01, 2013 @04:11AM (#43329045)
    Turn your phone off when you aren't using it. Do you really have to be contactable 24/7? I suspect not for most people and if your phone is off then you cannot be tracked.
  • by rew ( 6140 ) <r.e.wolff@BitWizard.nl> on Monday April 01, 2013 @04:17AM (#43329055) Homepage

    If you want to receive calls or SMSes, you need to leave the phone on and transmitting:

    When a call for your number comes in, the incoming call is NOT transmitted nationally. Only in the GSM-cell that you are actually in is the signal transmitted. So, the system has to know in which cell you are to be able to "call" your phone. If you properly turn it off, the phone will tell the GSM network it is going off. So when a call comes in, it will go to voicemail immediately. If you yank the battery, the system will assume you are still in that cell where you last had the phone on, but it will probably time you out if it doesn't hear from your phone for a while. (which happens naturally if for example you drive out of range).

    • by KiwiSurfer ( 309836 ) <james&pole,net,nz> on Monday April 01, 2013 @05:27AM (#43329257)

      When a call for your number comes in, the incoming call is NOT transmitted nationally. Only in the GSM-cell that you are actually in is the signal transmitted. So, the system has to know in which cell you are to be able to "call" your phone.

      Not quite, a GSM switch will keep track of which Location Area (LA) a mobile device is in. A LA can contain a few or upwards to several hundred cells. Using Vodafone's GSM network in New Zealand as a point of reference, their largest LA covers all of Auckland's (our biggest city with 1.5m population) CBD with around 150-200 sites while in rural areas a LA generally only has around 50 sites.

      When a phone is being called, all the cells in the LA will send out a broadcast request to all mobile devices in the LA and the mobile device will respond by contacting the nearest cell. This is quite useful as it reduces the need for the mobile device to check in frequently — the mobile device only needs to check in with the network when it moves into a new LA.

      I'm not too familiar with how UMTS or LTE works but I presume the same principles applies but I may stand corrected.

      • by rew ( 6140 )

        The cell-phone transmit is "expensive" in that it drains the battery. You can optimize the electronics all you want but if you have to transmit a 1W burst for 0.01 seconds to indicate that you're still there, the energy expense of that burst is fixed and cannot be reduced. This is apparently a trick to reduce the number of transmissions from the phone to the towers so that the battery can last longer. I didn't know that. Thanks for the update!

        • by rew ( 6140 )

          On second thought:

          As a privacy concern the fact that "the network" knows where you are is a problem.
          It does not matter whether the network knows your location to 3m (your phone sends the current GPS location), several tens of meters (your phone reports the strenghts of several towers it "hears"), several hundreds of meters/ a few km (which cell) or several tens of km's (the LA).

          Track the LA's of my phone and you'll know when I visited my mom last week. Sure, you'd have to guess that I actually visited my mo

  • Futile (Score:3, Informative)

    by Anonymous Coward on Monday April 01, 2013 @04:18AM (#43329059)

    You can't.

    Those are functions performed by the baseband software stack, which cannot be modified by the end user. Also you can't be simultaneously connected and not connected to the network anyway. If you don't want to be tracked by the network, don't use a cellphone.

  • I suspect that's the answer you were looking for, but i'm afraid that's not an answer. Something like this would probably require hardware switches to be truly effective. It's much simpler to take out your battery as a few others have already stated. and dont forget to discharge the device by holding in the power key for a good 10-15 seconds.
    • How do I remove the battery from my iPhone???? PLEASE HELP ME! They are afters me!
  • by asnelt ( 1837090 ) on Monday April 01, 2013 @04:25AM (#43329081) Homepage
    I would say a good start is to just use the airplane mode of your phone. That should disable your RF transmitter. But of course you wont be notified when the network is paging your IMSI. The save option is to use a phone with OsmocomBB, a free software implementation of the GSM stack: http://bb.osmocom.org/trac/ [osmocom.org] It has limited functionality (no GPRS working at the moment) but at least you know exactly would your phone is doing. With that, you can even run CatcherCatcher, which is able to detect IMSI catchers: http://opensource.srlabs.de/projects/catcher [srlabs.de] The supported phones are a bit outdated, mostly old Motorola phones. But there is one supported smartphone: the Openmoko Freerunner. It is pretty usable these days and is fully supported by Debian. I love it, but you will need to tinker - a lot.
  • by qaz123 ( 2841887 ) on Monday April 01, 2013 @04:58AM (#43329167)
    - Buy it using a fake id. - Ask a homeless or drug addict to buy you a prepaid phone/sim and use it. - Buy it in another country.
    • by pla ( 258480 ) on Monday April 01, 2013 @05:48AM (#43329321) Journal
      Buy it using a fake id. - Ask a homeless or drug addict to buy you a prepaid phone/sim and use it. - Buy it in another country.

      Actually one of the most realistic answers so far, except, you don't need an ID or a straw buyer... Just pick up a tracphone at Target and activate it at the in-store Starbucks' hotspot. Done and untraceable-to-you, unless "they" want you enough to manually hunt down security footage from one of those two stores.

      That said, who do you plan to call with it? I consider it a sad commentary on our times that who (on the whole) you associate with matters far, far more than your own identity - Though the two end up largely interchangeable, unless a lot of people in your immediate circle of friends call to chat with your folks once a week. And of course, you probably use it at home - Lot of people living there? Keep in mind, even pre-GPS requirement, the cell providers could still get a decent lock on a phone just from the towers that can see it; and going back to the original FP question, you can't use the phone if no towers can see it.
  • by AHuxley ( 892839 ) on Monday April 01, 2013 @05:15AM (#43329217) Journal
    Phone tracking was a result of the troubles in Ireland and the NATO/US need for Red trouble makers in 1980's Europe.
    Think of an early Cyber Intelligence Sharing and Protection Act (CISPA) hardwired into every generation of phone by default.
    Then came GPS, web 2.0, maps and cloud ... your phone is sucking up details about your life as you walk around with/use it.
    Stop using your phone other than for family to say hi and ask for help/shopping.
    Meet your people/tribe/business associates without a phone and talk face to face or in some other hi tech/no tech way.
    Soon a working phone with CCTV (camera pod), facial recognition, 24/7 city wide look down drones, covert LEO in-car cameras will be filling in even more details.
    Dont forget the private sector is also doing its part to link all their cameras in too :)
    No warrants are needed. Deep extended boarder search, gang area 'random' searches, drink driving tests will all have rows of plate reading cameras, passenger face capture, driver logging, train station federal task forces, anti war mil protest watching... all add up to very deep efforts if you make a list.
    All the tech used in 1950's Soviet watching, Vietnam, Iraq is now so cheap, tiny and sold to even the smallest, struggling police forces as federal 'gifts' to help with 'drugs', 'terror' or just as free 'surplus' with never ending private maintenance contracts.
    The next big thing will be state level voice print records- no longer the play thing of GCHQ, NSA - expect a fake cell towers in a region of interest to do more than just log calls, numbers and record flagged people - your voice will soon be all that local law enforcement needs on any network.
    Swap the phone sim all you want, better stay off the voice too.
    • All you did was provide a few concrete examples of the issues the submitter posed, and threw in some buzzwords. How are you remotely Insightful?

      • by AHuxley ( 892839 )
        What can you do? Every message you send if you phone is flagged is logged, every phone connecting to a flagged phone is logged.
        When a clean phone connects it is tracked, when a known phone rings out to a clean phone your logged.
        So both sides have to swap clean phones details and change phones quickly without infiltration or plea deal along the sim supply line- dealer, courier, contact...
        Then you had the "performance monitoring and diagnostic tools" layer added by helpful third parties to hardware that j
    • Actually in the US, mandatory tracking was put into place as part of enhanced 9-1-1. There were a rash of emergencies where the caller couldn't be located in a timely manner (IIRC one was a lady stuck in a car during a blizzard in the midwest). The law required phone companies to be able to give a location within 300m no later than 6 minutes of the request by a public safety answering point (PSAP). Radio location capabilities on the towers and GPS built into phones were a direct result of this law.

      What the

    • by gl4ss ( 559668 )

      blahblahblah.
      the made an efficient mobile phone network just so they could fuck with separatists? because the trackability is a byproduct - can't have one without the other.

      and if it's "them" the official authorities doing their thing.. they don't actually need fake gsm towers. why the fuck would they? you only need them if you want to go without warrants or asking for authorization... which is pretty much why they should be(and well, they are technically!) banned.

  • by complete loony ( 663508 ) <Jeremy,Lakeman&gmail,com> on Monday April 01, 2013 @05:20AM (#43329237)
    So don't use your cell phone as a cell phone. Buy a pre-paid with no ID (if you can), use the data connection to open a VPN link, use whatever voice and IM protocols you want over the VPN link.
    • by gl4ss ( 559668 )

      if you use it as a data link they can still see where you are.
      if they're really tracking the guy then can deduce which imsi it is that he is carrying with himself with couple of days of surveillance.

      of course by that effort they could just slap a transmitter on his car as well.

  • As stated you cannot turn off the transmitter and have the network be able to reach your phone. However you can get a smartphone with good custom rom and kernal support. Then you can build your own kernal and be sure it has a real gps switch. You may also be able to implement filtering of the network stack bit iirc, the radio section is often a binary blob. Find a phone where you can code all thos and you may have a popular product.
  • by thegarbz ( 1787294 ) on Monday April 01, 2013 @05:32AM (#43329271)

    Even with GPS disabled or if your phone doesn't have GPS, cell triangulation allows for a reasonably accurate position of the phone. In urban areas this works well, in rural areas less so but still enough to provide someone with potentially useful information. This is a function of the cell phone network and not the GPS of your phone.

    • Comment removed based on user account deletion
      • by DontScotty ( 978874 ) on Monday April 01, 2013 @06:18AM (#43329413) Homepage Journal

        If you are only using one tower - sure...

        --------
          The tower can also measure how long it takes to get a response from your phone, and use that to estimate how far away you are. That puts you on the edge of a circle that distance from the tower.

        Usually your phone can be heard by multiple cell towers. If two can hear you, then you're on the edge of each of 2 circles, and two circles can only meet at 2 points, so you must be at one of those 2 points.

        If a third tower can hear you, its circle can only meet the others at one point, so there you are.

        Emergency services (like 911) can get this information from the cell towers. The information exists whenever your phone is on and in range of a tower, whether you're making a call or not. The information is not meant to be publicly accessible.

        • The actual process is called "trilateration", if I haven't botched the spelling. Sprint was claiming 1000 meter accuracy minimum.

          If you can't get at least 3 towers, you have to fall back to less accurate options. I'm not sure if the 2-tower approach is employed or whether they simply take the easy way out and look for the tower with the strongest signal. I suppose it depends on provider and local equipment.

      • by AHuxley ( 892839 )
        Re much as 10 miles.
        With logs, a good security system in place and pro police level tech skills - you can get that down to streets, cars.
        http://www.slate.com/articles/news_and_politics/war_stories/2006/07/italys_watergate.html [slate.com] showed in open court what good team can do with cell information.
      • And it can be pretty damn accurate, too. Older iPhones didn't have GPS and relied on trilateration to navigate in map applications, and I remember it being surprisingly accurate.

    • Suppose you hacked the GPS software stack to fake your location - e.g. shift it northeast by 50 miles. Would the various location-finding services use the GPS location, or the triangulated radio tower one? Or, would the software notice the discrepancy?

      • Most android phones have a feature to "allow mock locations". This allows programs special access to write location data to the phone and is how some bluetooth GPS receiver apps work. This is a godsend for my original Galaxy S with it's crap GPS receiver which doesn't work in the car. I use an external bluetooth serial GPS unit for navigation.

        I don't think software is smart enough to notice a discrepancy between cell location and GPS location as it would have to make some risky assumptions on where you are.

  • by Simon Brooke ( 45012 ) <stillyet@googlemail.com> on Monday April 01, 2013 @05:37AM (#43329291) Homepage Journal

    Curiously enough I saw an idea to solve this problem [ahprojects.com] this morning. It's a small bag lined with material opaque to radio waves (possibly lead foil or barium, I don't know). Whether this particular implementation works or is a tin-foil beanie, again I don't know. But the concept seems to me good. With modern phones like iPhones or my HTC One, the battery is non-removable, so it isn't easy for the user to verify that all radio transmission is in fact shut down - there could still be things like, for example, passive RFID. But if you had a radio-opaque bag in which you kept your phone, you could have a phone with you in case of emergencies, without the possibility of being tracked except when you were actively using it.

  • http://www.schneier.com/blog/archives/2013/03/our_internet_su.html [schneier.com]

    But... if I were going to try and confound the system which can correlate almost all of your electronic records, you'd need to have a rolling list of sock-puppets who supply proxy identifying information to the cell towers. You'd need to have a bundle of SIM cards in the handset to do this, or to have electronics which fake the same data. Then, to make sure you can actually be contacted, you need to have a call redirection system sending you

    • I have heard about mesh networks, for instance, B.A.T.M.A.N. or Netsukuku. You just need a mesh network to GSM gate that impersonates your phone and sends the calls via the mesh to the endpoint router with VoIP gate. It's quite difficult to trace the mesh but all this project needs at least tens of paranoiacs around the city that keep the mesh routers up and running.

  • ...when they just turned the border pink and we talked about... OMG Ponies!

  • As I have mentioned before:

    Dear Editors,

    There is an 'Ask Slashdot' section for a reason. Please use it!

    Thanks.

    Fnord666

    PS Putting "Ask Slashdot" in the title doesn't do it.

  • Both ways. RF can't cross the cage either direction.

  • by argStyopa ( 232550 ) on Monday April 01, 2013 @07:08AM (#43329625) Journal

    Seriously, if you're that paranoid about being traced, why even carry a cellphone?

    Essentially, if you're going to turn off all the functions that allow connectivity, and disable the phone enough that you're *pretty sure* that you can't be traced, why are you even carrying it? It's going to be a non-functional pile of circuitry in your pocket, basically. If you're that concerned, then any time you turn it on you might be being traced, even if the radio function is allegedly "off".

    I guess if you want to be able to call out in case of emergency, just buy a one-time phone and DON'T USE IT UNTIL YOU NEED TO. Then throw it away.

  • My solution is to stay a Sprint subscriber, that way I am never near any towers and if I see more than 2 bars I know the FBI is close.
  • The only really secure way to turn of a smartphone is to remove the battery. Get one where you can do that or mod it with a switch.

  • US Patent 7751826 - Motorola submitted the patent in 2002, it was issued in 2010:

    US Patent 7,751,826 [google.com]

    The Federal Communications Commission (FCC) has mandated that, by December 2002, all cellular telephone carriers must market handsets capable of providing an emergency locator service. This emergency locator service, known as E911, will enable personnel at the public safety answering point (PSAP) to pinpoint the location of a cellular telephone user dialing 911. This FCC mandate further requires that the user not be able to override the emergency locator service in the case of a 911 emergency call.

    This technology has raised public concern that, in addition to being used for emergency location, the locator service may be used by cellular carriers or by others to track the movements of cell phone users without their consent. There is therefore a need for a system that complies with the FCC mandate for location service while providing maximum privacy protection for cell phone users.

    The invention overcoming these and other problems in the art relates in one regard to a system and method for selectively activating or deactivating E911 tracking service, in an embodiment by disabling power to GPS locator circuitry in a cellular telephone until the key sequence "9-1-1-Send" is detected. In one embodiment, the power to the GPS circuitry in a cellular handset may be activated by detection of a keypad sequence and the rotation of a physical switch to permit power delivery. When the handset detects the key sequence "9-1-1" it may output a signal that loads the switch into a "ready" position. When the user presses the "Send" button, the switch closes, enabling power to be delivered to the GPS circuitry. In other embodiments, the selective delivery of power may be controlled by software.

    Motorola has been building phones for more than a decade in which the GPS circuitry is physically separated from electrical power until the user does something that causes it to be connected. This obviously doesn't help you if your phone has been hacked or modified and it doesn't help you avoid network triangulation, but it makes you wonder how all these supposed experts know all about the "dangers" of cell phones without having done much research or talking to the people who actually made the phones (you know, the inventors of patents are listed on the patents).

"Oh what wouldn't I give to be spat at in the face..." -- a prisoner in "Life of Brian"

Working...