I’m investigating getting off the cell network permanently to avoid at least the constant triangulation of my position. I figured I’d look into getting a VoIP number and getting calls and texts over WiFi. I don’t mind being unreachable when I’m not connected to a hotspot, so it’s not a problem for me.

But before looking for a good VoIP provider, I decided to check if WiFi still worked in airplane mode. And indeed it works. But to my surprise, when I connected the WiFi, my cellphone provider’s name also came right back up at the top right of the screen. In airplane mode? What the hell?

Long story short, after investigating a bit, I realized I had WiFi calling enabled. So I can in fact already get calls and texts without being on the cell network.

And I’m thinking, maybe that’s good enough for privacy?

I mean I know SIMs leak information like ICCID / IMSI / IMEI so obviously they have no reason not to do that over WiFi also and that’s not so hot.

But on the plus side, none of that information is linked to cell towers and location anymore - at least not precise location if I’m not on a VPN - the baseband processor is off and can’t do whatever shady chit-chat it does with the SIM and the cell towers, and I can still use my normal phone numbers without having to change and tell a million people that I have new numbers if I go with VoIP.

Also, I don’t store my contacts on my SIMs and I use a deGoogled Android. So I figure that limits how much adversarial software can exploit the SIMs to leak data.

So it seems to me that WiFi calling may be a good solution for me for better privacy without too many compromises.

Can you think of something I missed that I should know before using this feature?

  • TerkErJerbs@lemm.ee
    5·
    2 months ago

    I’ve used wi-fi calling fairly extensively mostly because I’ve lived in areas where there was zero cell service but ready access to internet (via Starlink or other wireless forms of it). One thing I do know is that my phone co. requests that I fill out a form specifying where I am living currently (whilst using it) so that if I ever need to contact emergency services they’ll have a better idea of where to route the call to. For instance my phone number originates from Western BC but I could potentially be using wi-fi calling from anywhere in the province. I mention this to say, it appears my telco doesn’t have a way to triangulate me with this service.

    I can further attest that wi-fi call & text reception still works fine when I have a VPN running on the router that my mobile device is connecting to. Make of that information what you wish.

    Though that I have read that wi-fi calling is atrocious for privacy reasons that I have not followed up on. Given the above I’m not sure how or why that would be the case, but basically if I’m in an area with cell coverage I turn it off. I’ve always meant to look deeper into how or why it might be bad (or worse) in some way.