[Nextgrid]

Unfortunately phone manufacturers (even Apple) are in bed with the carriers and still don't provide VoIP as a first-class option in 2022. VoIP is not as well integrated into the OS as normal cellular calls are, and you can't verify a VoIP number as outgoing number for iMessage/FaceTime either.

[denton-scratch]

> phone manufacturers (even Apple)

Oh, that kind of phone. Apple doesn't make "phones"; they make mobile devices.

We were speaking of fixed-location phone services. You don't need a mobile device to do fixed-location telephony; my VOIP-phone is made by Gigaset. It doesn't do iMessage/Face-whatsit, but neither do I.

I'm usually at home; I wouldn't need a mobile device, except that some commercial and government services refuse to believe I exist unless I can spit out a mobile number. I don't carry my device with me; it lives on my desk at home.

In terms of standard voice telephony, my Gigaset phone works better (and is much cheaper to use) than my mobile device. And the battery never goes flat.

[Nextgrid]

The problem with a non-iMessage/FaceTime capable phone is that you sacrifice confidentiality and quality. Unless both sides are a good VoIP provider that interconnects with others over IP (which would ideally pass through RTP as-is and allow both sides to negotiate a good codec like Opus) - which is unlikely among the non-technical crowd - you're stuck with a fairly narrowband codec, where as FaceTime is something everyone has (and Android has its own options, including cross-platform ones).

[29083011397778]

Hell, even Android, which had built-in VOIP support in the default AOSP dialer app, had VOIP support ripped out. It now requires a third party app.

[Nextgrid]

Since LTE and IMS, all phones internally have a built-in SIP client already. If you're on LTE or using Wi-Fi calling, you're using SIP under the hood. There is no reason that client can't be opened to allow people to add arbitrary SIP accounts if it wasn't to protect the carriers' monopolies.