It could also be something less alarming, like cellular repeaters inside the building. Many buildings use these to boost indoor coverage when concrete and steel block signals from outside towers, and that might explain why your phone flagged multiple connections so quickly. I’m not ruling out the possibility of a rogue tower or IMSI catcher, but it’s worth considering that the alerts could simply be repeaters being picked up by this new warning feature. Either way, it’s good that your phone is making you aware — at least now you know when unusual connections happen.
this post was submitted on 02 Sep 2025
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A cell phone repeater is a passive device. It just extends the range of an existing signal. They don't act as cell towers. They don't read information from the phone.
That’s true for some types of signal boosters, especially the simple passive ones. But many building systems aren’t just passive repeaters — they use distributed antenna systems (DAS) or active repeaters that re-broadcast the signal from outside towers. From the phone’s perspective, those can sometimes look like a new connection point, even though they’re not rogue towers reading data.
So while your point is absolutely right that a normal repeater doesn’t act as a tower or capture phone info, the way modern indoor coverage solutions are implemented can still trigger the same kinds of warnings. That’s why it can be hard to tell apart a harmless booster from something more suspicious.
More information about DAS systems and cellular repeaters, and how they differ, if you’re interested:
🔗 https://en.m.wikipedia.org/wiki/Distributed_antenna_system
🔗 https://en.m.wikipedia.org/wiki/Cellular_repeater
(edit, added Wikipedia links)
If you switch off 2G, bear in mind that it might be your only option to send emergency calls when otherwise out of signal. Remembering how to switch it back on (or even that you'd switched it off) might not be feasible when you need it!
edit: phone typos
According to the documentation, turning off 2G will not block emergency calls. But, yeah, having said this, definitely, it's best to remember how to switch it back on, just in case.
Can confirm. The Setting on my Pixel 7 says "Emergency calling is always allowed"
I'm illiterate to these things sort of... So don't harangue me for this but doesn't that imply that the connection is always on wether you disabled it or not? Would not outgoing imply incoming as well?
Just curious, again, I have no idea.
As I understand your phone will ignore 2G requests unless it's an emergency call. Now, you mentioned these suspicious towers will try to downgrade to 2G, which should also be ignored.
US carriers have supposedly decommissioned 2G completely as of February of this year according to Google:
Carrier shutdowns: All major U.S. carriers have shut down their 2G networks. AT&T completed its shutdown in 2017, Verizon in 2020, and T-Mobile (the last major holdout) by early 2025.
2G is shutdown for consumers, it still exists for commercial systems that use it for data reporting (thing gas lines, remote monitoring systems, etc).
Now I don't know what that means for our phones, or which towers still have it. I suspect any consumer phone will simply never be able to connect via 2G,but the tower would still see the phone on 2G.
A few years ago someone I knew at T-Mobile said they could no longer get replacement parts for 2G equipment. If it's still up and running I wonder how it's being maintained? Or maybe he was misinformed.
That's hilarious. No major facilities-based mobile network provider in the US has used physical 2G hardware for many years.
Everything was converted to software-defined remote radio heads long ago. The RRHs get mounted up in the air directly behind the antenna element arrays. The same RRHs that power LTE RANs can do GSM just fine.
GSM is computationally and spectrally an afterthought. They literally shove it into the guard bands at the far edges of the PCS LTE carrier.
Found and updated the avoid 2g setting on my Pixel 6. I am running android 16.
Where was it? Haven't find it on mine
Network and internet>internet>settings button next to carrier>scroll to bottom
Thanks!
For me it was in my SIM card settings: Network & Internet > SIMs > .
Bottom option was a toggle for "2G network protection".
I think this change needs hardware-specific code changes, so not every device upgraded to Android 15 or newer will have that
I am aware, but the person I'm replying to mentioned a specific device, which I also have.
It tries to force you down to 2G
Oh shit... Could this be why my phone seemingly randomly switches to 2G/LTE? It always seems to happen in the same places, and never for more than a minute or two.
No way to tell but the best practice is to keep your phone LTE or 5g only.
I had a discussion recently on here about it.
My understanding is LTE is best since it can't be used to exact positioning and saves battery.
However apparently it has its own security vulnerability that 5g fixed. However 5g can literally expose your special position.
Either way never prrmits 2g/3g that's just fish bowling.
That's fucking creepy, and I've got a feeling that we're going to see a lot more of this going forward, too.
Are there any known ways to detect or interfere with Stingray devices? I know that in the US, police often use these devices illegally, without the necessary warrants, so sabotaging these devices is a just and moral decision.
In the U.S. it's illegal to do anything that would interfere with these devices because it also cuts off emergency services. Sort of like using a hospital to store weapons during a war?
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Turning off the phone doesn't stop it? How does it reply?
I'm assuming pulling my (Fairphone) battery out would kill it dead?
Creeeeeeepy
I don't seem to be able to even disable it on this phone.
https://github.com/undergroundwires/privacy.sexy/discussions/359
The setting toggle seems to be available since Android 12, but not all vendors seem to have implemented it. There are instructions in the linked GitHub issue that seem sane.
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IMSI catchers / rogue cell towers do not work with switched off phones or in airplane mode. Source: https://shop.mobilen.com/everything-you-need-to-know-about-imsi-catcher-detector/
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Even better, that means we can locate them.
What app is providing this service for you?
It's a new feature in Android 16, but older phones don't have the hardware to support it.
Very interesting, do you happen to know what the hardware it requires is?
My understanding is that the phone requires a modem that supports version 3.0 of Android's IRadio hardware abstraction layer (HAL). Older phone's modems do not support version 3.0.
they only know your phone is there, not that it's you. they also need to triangulate your position to know it more exactly than "it's in range", which requires special hardware with an extra antenna
They can triangulate from the 8 readings that they did and know my location. They also know it's T-Mobile and they can subpoena T-Mobile and Google to get the information (the IMSI code will identify the dealer) to identify who bought the phone and what phone account pays for the service.
Is this a new feature?
Is it coming to android 16?
It's in Android 16 for the first time, which is what the Pixel 10 ships with, but older phones don't have the hardware: https://www.androidcentral.com/apps-software/android-os/android-16-can-tip-you-off-if-someone-is-snooping-on-you-using-stingray-devices
You’ll also be able to shut off 2G entirely, cutting off one of the easiest ways for snoops to get in.
Damn is this also a new feature?
I didn't realize stock won't permit this. Wtf
Who the fuck still uses 2G? I thought even 3G had been turned off for quite a while by now...
Spooks force you to down grade into 2g/3g so they can capture your traffic data
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Really creepy.
2G has been phased out on current US networks but is still in place on our phones. I wonder what steps they'll take to access our data when 2G is phased out on the phones themselves.
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