EE isn't just making this up -- providers in other parts of the world already support Enhanced HD Voice, also known as Enhanced Voice Services. The upgrade from HD Voice promises not only to improve call quality, but also reliability. Naturally, it'll only be available when a 4G or WiFi connection is, but there's another catch. For now, it only works on the new iPhone 8 and iPhone 8 Plus, which just happen to launch in the UK today.