> My Verizon iPhone has both a public IPv4 address and a public IPv6 address.

How are you able to tell with IPv4? You cannot run ifconfig on an iPhone, so how are you determining that?

There are apps like "Network Analyzer" that give you this info. (My MVNO puts me behind CGNAT, no IPv6)

Seriously? On Android it's just settings->about phone

Really? My Verizon Android gets RFC6598 space.

Holy cow, I don't know how I was never aware of RFC6598. When I saw the address starting with 100, I simply assumed it was an actual routable IP.