I think people should be aware that Airplane Mode on Graphene OS doesn’t completely turn off the SIM, as you still can receive and make calls over WiFi, a technology known as Vo WiFi.
I am not certain about it, but I think this means your ISP can know your location, at least when you stay home (Vo Wifi might only work on router from the same ISP as your mobile).
You can disable it in your SIM settings.
Only if your cellular provider supports this, right? I mean, this is very easy to test so folks can try it out for themselves and see what works and how if at all.
Probably, if they see the IP address of the wifi.
If you use a VPN, its maybe a different situation.
Probably / might bypass it
I don’t think your exact location gets exposed with VoWiFi (because you’re not connecting to a cell tower in aeroplane mode), but your IP is; even with a VPN enabled because Android doesn’t tunnel some connections, including VoWiFi, through the VPN.
But I’m pretty sure you can turn VoWiFi off in the carrier settings.
Are you saying that airplane mode on stock android does not work in the same way?
Airplane Mode on any smartphone generally means turning off cellular radios, not WiFi.
This issue is well documented in the GrapheneOS documentation. It is an upstream issue with Android, but I do believe GrapheneOS is working to ensue ALL traffic from the phone goes through the VPN tunnel. If you need your IP address hidden, you need to turn off wifi calling.
I also am pretty certain that if you use a VOIP number that goes through the VPN tunnel.
I am pretty sure your ISPs can correlate router IPs with exact location.
I have no idea honestly,. I saw on this forum a table linked where it mentioned VoWifi as a GOS convenience feature.So this seemed to mean that they are aware of this, (response to @dadnerd)
I think this post was relevant because some people seem to equate Airplane mode with SIM off. At least I did. That’s not the case. Just worth remembering. Wish there was a ‘disable all sims’ toggle (yes, you can disable them in settings but it isn’t very convenient)
I recommend reading all the info on their page. Specifically the default connections and other connections section in the FAQ. If you need security and privacy, you need to know how your OS works. The graphene team is VERY transparent and clear about what Android issues they’ve hardened, and which issues remain vulnerable.
This is actually exactly what I thought airplane mode was on GrapheneOS, because airplane mode is intended to disable cellular radios, not your SIM, as is well-documented and how it works on every mobile OS.
Likewise, disabling your SIM does not disable your cellular radios and your device will still ping cell towers, unless you enable airplane mode.
It’s in the name, really. Airplane mode exists solely to comply with regulations requiring cellular radios be completely turned off on airplanes. The privacy factors are a side effect. There’s no reason for it to disable SIMs too in this context.
Maybe GrapheneOS could add a feature to also disable the SIM when turning on Airplane mode, but I am not sure if this is technical possible