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Androids caught secretly reporting location data regardless of opt-out

Androids have been collecting our location data and sending it to Google when connected to the internet

Android users, are you wary about being tracked via your phone’s location data?

…So worried that you turn off location services for apps in your settings?

…So cautious that you haven’t even inserted a carrier SIM card?

Well, that’s all been an exercise in futility!

A new report from Quartz has discovered that Google’s been collecting the locations of Androids (and therefore their users) – triangulating them via nearby cell towers.

Quartz tested it on devices that had no apps installed, that lacked SIM cards, and that had location services turned off.

Google has confessed. Yes, it said when contacted by Quartz, it’s been calling home with cellphone tower data since January 2017, in spite of our privacy concerns and the preferences we stipulate in settings.

A Google spokesperson told Quartz that Android devices have been sending the addresses of nearby cell towers as part of the system Google uses to manage push notifications and messages.

The location data was never used, and therefore was never stored, according to the spokesperson. (If you don’t find that particularly comforting, too bad – it’s not possible to disable the feature.)

However, the spokesperson told Quartz that Google is “taking steps to end the practice… at least as part of this particular service.” Google didn’t say whether there are other Android services that do this, but it did say that Android phones will stop snarfing up cell tower location data by next Thursday.

It wasn’t a bug, the spokesperson said in an email. It was intended as a way to grease the wheels of our messaging!

In January of this year, we began looking into using Cell ID codes as an additional signal to further improve the speed and performance of message delivery. However, we never incorporated Cell ID into our network sync system, so that data was immediately discarded, and we updated it to no longer request Cell ID.

The finding pertains to all modern Android devices. Quartz talked to a source familiar with the matter who said that Google started collecting the cell tower addresses after it changed its Firebase Cloud Messaging service, which is owned by Google and runs on Android phones by default.

Quartz observed the location data being shared even on devices reset to factory default settings and apps. Mobile phones keep in touch with the cellular network even if you don’t have a SIM card inserted, which is why you’ll see a signal strength indicator even when you’re not able to make calls. So, Google gets data every time a device comes within range of a new cell tower, and as long as the device has internet access – even if you’re only connected over Wi-Fi- Google can call home with that data.

You don’t have to look far to find instances where location data has been used in surveillance scenarios in which the information of scads of unintended targets gets caught up in dragnets. One of the most notorious such dragnets was revealed by Edward Snowden, when he released documents that showed that the National Security Agency (NSA) was collecting and storing data in a vast database that contained the locations of at least hundreds of millions of devices.

Nevertheless, there’s no evidence that Google was up to no good, and therefore no obvious reason to distrust the statement that the data was submitted but discarded.

After all, after the Google Wi-Spy scandal – where Street View cars drove around sniffing out Wi-fi network names but accidentally saved additional data fragments along the way, soemtimes including passwords, usernames, email contents and so on – you’d like to think that Google wouldn’t keep data it wasn’t directly using.

How does one avoid being tracked by cell phone towers that track you even with location services turned off? Most consumers would likely imagine that powering down their handsets should prevent it from emitting or receiving a signal. They might be wrong.

With Snowden’s release of documents, the possibility arose that the NSA can even trace a phone that’s powered off. In fact, the US State Department’s Bureau of Diplomatic Security in 2013 warned those traveling to the Winter Olympic Games in Russia to be extremely cautious with communications. The department’s list of precautions included removing batteries from phones entirely when not in use. Snowden himself told people to store their phones in the refrigerator, given that it’s a Faraday cage that blocks electromagnetic fields.

So there you have it: if you’re really worried about tracking, it seems you only have two choices: de-batterize the sucker, or get your kitchen appliances to shut it up.


> Mobile phones keep in touch with the cellular network even if you don’t have a SIM card inserted, which is why you’ll see a signal strength indicator even when you’re not able to make calls.

Actually, you can make emergency calls (911 in the US) with no SIM.

> Quartz tested it on devices that had no apps installed, that lacked SIM cards, and that had location services turned off.

Ahh, but did they test it under the case where the user has first entered Airplane Mode (turns off cellular, Wi-Fi, and Bluetooth) and then has turned Wi-Fi (only) back on? This has the effect of leaving cellular disabled while enabling Wi-Fi. If you had no SIM it would be the smart thing to do, since it substantially conserves the battery.

Thanks for breaking the story, but I hope you will get back to your sources and come back with a more complete report.


Two comments…

We were going to add some words about “making emergency calls with no SIM” as a convenient way of reminding people that you are still in touch with the mobile network even if you aren’t authenticated to it. But we decided to leave it at “seeing the network strength” because you *can’t* always make emergency calls with a SIMless phone. For example, the UK (AFAIK) banned SIMless phones from making any calls a few years ago because of the abuse of burner phones to make untraceable calls to waste the time of emergency services. (You can make a 999 or 112 call with no credit and with the device locked, but it must have a SIM.)

I am sure you are right that if you turn off GSM but have Wi-Fi turned on you are OK, because your device won’t see any mobile towers so there won’t be any mobile network ID data collected in the phone for the software to suck up. AFAIK on stock Android the only way you can do that is as you describe: turn Airplane mode on (which forces Wi-Fi off) and then turn Wi-Fi only back on. That would stop Google knowing your closest cellular tower, whether you had a SIM installed or not.

My own personal opinion, admittedly based on hearsay rather then direct evidence, is that Google is telling the truth here and that the collected cell data is transmitted but discarded. If I were going to sweat about some sort of location data being collected regardless of my location settings, I would worry more about the mobile phone companies – their towers know where my phone is whenever the radio in on, apps or no apps, Android or not.


So are roms like Lineage OS without G-Apps affected? I wouldn’t think so but just making sure I understood correctly.


I can’t see how LineageOS itself could be affected on its own, with no proprietary Google apps installed.

I am also prepared to risk a guess that if you have (say) just the “pico” version of Open Gapps, which is pretty much enough to get the Play Store app only, you are immune, too.

Anyone know for sure?


Can it get any more spy vs spy crazy… phone is off and still broadcasting location!, I’d like to see notes from the team that implemented that. Was it the NSA dept of google, or just google. This must have been built into the hardware from the start to be possible. I smell a deep pit of conspiring to track people from years ago. I wonder how far back in Androids history this goes, and who approved it


No, no, the phone is *not* off. That’s the whole point.

The phone, including the cellular radio, is *on*. And when your phone’s UMTS/GSM mobile radio is turned on, it communicates with the mobile network so the phone knows the nearest tower and the tower knows where you are. That’s how UMTS is supposed to work, always has.

At this point, it’s Google’s software that leaks the cell tower data that your phone knows because the radio’s on.

That behaviour is definitely wrong, but it’s not exactly the stuff of conspiracy theory, and this leak doen’t happen when the phone is off.


I was referring to the next to last paragraph “the NSA can even trace a phone that’s powered off.” Which I guess is a statement and not a fact.


Ah. Sorry. I see that now.

Actually, that bit says “with Snowden’s release of documents, the possibility arose that the NSA can even trace a phone that’s powered off”. My brain autodeletes sentences like that because they serve no intellectual purpose that I can find. What sort of phone? How big is the possiblity? How on earth did the possibility of being traced arise as an outcome of the leak? Not sure what Lisa meant. Perhaps, “Snowden’s revelations included claims that the NSA could track some types of 2000-era cellphones after they’re turned off.” I think that much (the claims) is true. No idea whether those are facts rather than merely claims, or if any it applies to the Android devices described here – my gut feeling is, “No.”


Interesting. What about contract and government employees going on the job to work locations where the combination of person and location is classified? If someone thinks that turning off location is enough, then wouldn’t Google be keeping classified data on their systems? I personally turn off my phone and put it into a tempest enclosure when I need to. Co-workers called me paranoid, but it looks like I have the last laugh.


I believe a microwave is also a Faraday cage, so you could also put your phone in there if you’re out of space in your refrigerator or freezer. Just make sure to take the phone out before you try to cook anything, if you want to keep the phone & microwave. :)


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