[lxgr]

At least Vodafone Germany intentionally blocks (or used to block) foreign IPs for their gateway. I'll always trust them to needlessly ruin perfectly fine technologies.

Fortunately, as far as I remember at least iPhones route VoWiFi traffic over a VPN, if any is connected, so that's one way to still use it abroad.

[miki123211]

This is actually less unreasonable than it seems at first.

The Vo WiFi spec only defines handover procedures for networks that implement VoLTE, but VoLTE roaming was historically almost nonexistent, although the situation is improving somewhat.

This means that if you go out of range of your WiFi router, your cell phone has no idea how to request a handover from the network, and the call drops.

[lxgr]

By that logic, shouldn't they never have rolled out VoWLAN as long as they still have some non-LTE covered areas in Germany either?

Also, I'd much prefer a call getting dropped to suddenly changing from being included to billed when traveling abroad.