VoLTE is so damn frustrating. LTE works via plug and play with any phone that supports the correct bands, but VoLTE doesn't. I have a Sony Xperia phone here in Canada and it's just not possible to use it on VoLTE without rooting to install specific provisioning files and whatnot. And that's not even counting how you can't just go from country to country without changing firmware. I've always used a local SIM whenever…
VoLTE has been "broken" (from a standards perspective) since before it even launched in most markets - it is just too "finicky" and configuration-specific. LTE/4G demonstrated the success of standards in that it "just works" as long as you have the right bands in place. Since most (modern) phones have the bands needed for the main global markets, you can pop in a SIM card and get connected anywhere. VoLTE is far more…
Is there a way to find out which countries do this?