So if you initiate a call from cell (LTE, not FaceTime Audio) and that call gets turned into a FaceTime video call, are you stuck on LTE if WiFi is otherwise available?)

I presume that if the call began as FaceTime Audio (and on WiFi) then adding video later keeps you on WiFi?

Thanks

Since FaceTime is totally internet based, I would think it would be using whatever your current internet connection is at the time, but I have no experience with this.

Which makes me ask, how does one make this happen? My wife experienced this one day, she called into her office from her iPhone, it was to a landline number, somehow the admin assistant that answered transferred it to the person she wanted, and that person was on an iPhone and when they connected it switched to a Facetime Video call, which was totally unexpected and unwanted. Hanging up and repeating the process produced the same results.

Is this some sort of feature, is it documented someplace so I can understand what it's called and how it's supposed to work, and how to disable it?

Never heard of that. Sounds unnerving.

In my case, I initiated a regular call, they answered but then selected FaceTime and I got the notification to accept. We were both on WiFi but it didn’t matter. It became an LTE FaceTime, with predictably poor results (my LTE is only fair.)

In settings>cellular turn off FaceTime, then you can only use it over WiFi

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Roswell, GA (Atlanta suburb)

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rgG
In settings>cellular turn off FaceTime, then you can only use it over WiFi

Thanks. So the call will switch over to WiFi? I’ll have to try that.

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deckeda

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rgG
In settings>cellular turn off FaceTime, then you can only use it over WiFi

Thanks. So the call will switch over to WiFi? I’ll have to try that.

Not exactly but similar behavior, the app will report that it can't connect to the internet if it's not connected via WiFi.

The main purpose of those settings is to prevent apps from unexpectedly using Cellular Data for people on plans with monthly limits, which seems to be your concern too.

Yeah I get that. I imagine the challenge here is that audio and video are inherently continuous data streams. Switching back and forth automatically between LANs and WANs is OK for web browsing because “all” you suffer is a brief delay, while the browser and OS decides on the new Internet path. That behavior would likely just result in a dropped call or recipients giving up when 10-20 seconds rolled by and nothing happened.

Still, it makes me wonder if in fact there’s no mechanism for apps to engage in either LTE or WiFi handshakes for sessions already in progress via the other way. With WiFi it should be easier, because the Internet doesn’t care how you reached it, but with LTE if you walk out of your WiFi house on a WiFi FaceTime call, how would the cell carrier interpret that event as a “new call” in order to connect you, and connect you to whom? An iPhone user not on their network? Not gonna happen until Apple becomes a carrier.

Phone calls switch back and for the between WiFi and LTE without a drop in connection, I suppose FaceTime can do the same but I never tried it.

How do I make a WiFi call that's not FaceTime or some other app?

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deckeda
How do I make a WiFi call that's not FaceTime or some other app?

If your carrier and iPhone both support WiFi Calling, you enable it in the Settings > Cellular > Wi-Fi Calling setting. It will then use WiFi / Internet when available to connect to your carriers voice network instead of using the cellular tower voice service. Even works in "No Service" situations.



Edited 1 time(s). Last edit at 04/18/2020 11:11PM by GGD.