My carrier (NTT docomo in Japan) only provides IPv6 to the end device. Access to IPv4 servers is through DNS64/NAT64, where their DNS server rewrites any DNS re

My carrier (NTT docomo in Japan) only provides IPv6 to the end device. Access to IPv4 servers is through DNS64/NAT64, where their DNS server rewrites any DNS response that has an IPv4 in it to [64:ff9b::(the IPv4)] which gets handled by a CGNAT gateway. So anything that looks up a server over DNS and connects to that works fine, but any hard-coded IPv4 address does not. I presume Apples requirement is there so that all apps work on carriers like this. The only times I've run into issues is when tethering and forgetting I can't ping an IPv4, or trying to tether a Nintendo Switch (which does not support IPv6)