Mobile phone Wifi calling

Both Vodafone and Three allow wifi calling from some phones. The ability to make wifi calls via these operators appears to depend on the phone being used. So if a particular unlocked phone can make wifi calls via Vodafone, would it definitely also be able to make such calls via Three when using a Three Sim? Both Vodafone and Three publish lists of phones which they say will work but whilst the lists are similar, they are not the same.

In reply to a post by Michael_Chare:

Both Vodafone and Three allow wifi calling from some phones. The ability to make wifi calls via these operators appears to depend on the phone being used. So if a particular unlocked phone can make wifi calls via Vodafone, would it definitely also be able to make such calls via Three when using a Three Sim? Both Vodafone and Three publish lists of phones which they say will work but whilst the lists are similar, they are not the same.

If iPhone then yes, just change the SIM and you're good to go.

If Android then the answer is "it depends" on the software. In most cases EE works, but Three, Vodafone and O2 you have to test to see. Some phones (e.g. Samsung) you can change the firmware yourself to the customised mobile operator version.

The discount MVNO operators (e.g. Tesco, GiffGaff, Voxi) don't offer WiIFi calling. The odd ones out are BT, Sky, and I think Smarty.

O2 is a little tedious in that they allow wi-fi calling but only on pay monthly.

In reply to a post by Oliver341:

O2 is a little tedious in that they allow wi-fi calling but only on pay monthly.

I think it is only Three that enable WiFi calling on PAYG at the moment. Rumours are this is coming to EE PAYG this year.

As well as WiFi calling the other feature is 4G Calling (VoLTE) which enables calls over the 4G/LTE network instead of switching back to 3G. This works in a similar way to WiFi calling using the IP-Multimedia-System (IMS) stack at the network. Voice is just another data type over the LTE network.

However Android devices seem to need network customised software to support VoLTE.

Without VoLTE coverage on Three can seem awful. They have branded this "Super Voice" in their odd way.

In reply to a post by jchamier:

I think it is only Three that enable WiFi calling on PAYG at the moment. Rumours are this is coming to EE PAYG this year.

Handy to know. It's a shame this feature is limited for PAYG, I suppose it's part of the general thrust to get people on contracts.

In reply to a post by Oliver341:

Handy to know. It's a shame this feature is limited for PAYG, I suppose it's part of the general thrust to get people on contracts.

I disagree. To start with it was an unreliable service (back in 2016) but as people replace handsets and software updates, things have become stable.

Networks will want people on VoLTE so that 4G (and then 5G) data networks can handle the voice load, enabling the 3G signals to be turned off, and spectrum re-used for 4G / 5G, which is vastly more efficient.

Perhaps it is because PAYG users are on older handsets, which are replaced a lot slower, so would have a poor experience on VoLTE?

4G / 5G / VoLTE is all well and good, but when you have poor or no mobile signal it's a nice option to have to be able to connect to wi-fi and make a call/text over that.

Yes, and in new build homes and flats with the metal foil backed insulation in the exterior walls, you can have strong signal outside, and nothing indoors. WiFi calling is the only option.

Vodafone will still sell you a SureSignal box (femto cell), but the other networks might loan you a femto cell for a short time until coverage improves, if you are a "valuable" customer (ie, high spender). WiFi calling should get rid of all of this nonsense.

Much of the problem is Google didn't build standard WiFi calling or 4G calling into base Android, so each manufacturer handles each network settings differently. Apple built it in, so the individual network "carrier bundle" that is downloaded configures the settings.

The ancient iPhone 5s manages WiFi calling on EE and Three !!

Edited by jchamier (Fri 28-Feb-20 18:20:55)

In my experience (on EE at least) on recent handset firmware the UK generic (BTU) firmware as well as UK carrier firmware seems to work fine for VoLTE and VoWiFi.

WiFi calling is the reason I switched to EE about 6 years ago ......

My previous provider, Vodafone, gave such a bad signal indoors at the flat I moved to, that often even texts wouldn�t send . I rang and enquired about a Sure Signal, but they wanted too much money for it.

EE and WiFi calling on an iPhone has worked like a charm ever since.

I have BT Mobile for my work phone, it used to be that WiFi calls were only via an app (a pants way of doing things) but now it is a feature the same as with EE.