Voice over LTE and high definition calling is actually not the same thing. You can have a voice over LTE call and not have the high quality audio calling. All Voice over LTE actually does is make your call into packets between you and your providers network instead of setting up a circuit like they used to.
Do you mean VoLTE? It should work between different carriers afaik
Voice over LTE and high definition calling is actually not the same thing. You can have a voice over LTE call and not have the high quality audio calling. All Voice over LTE actually does is make your call into packets between you and your providers network instead of setting up a circuit like they used to.