Hey, magenta4494657! For the most part, non TMO devices won't be compatible with Wi-Fi calling because it requires T-Mobile WiFi Calling software to work. That said, most iPhones get a carrier update when they join the network that facilitates this, and we've also had users report some non-TMO phones working with WiFi calling. Officially, though, this would fall under the Non-T-Mobile phone & software disclaimer -- since we don't make the software, we can't test it and confirm that it's compatible. <3 I wish I had better news, but I'd rather be honest about it than have you disappointed!
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