Other forums read:
[Q] T-Mobile Wi-fi calling on 4.4 Roms (GE and Sense based)
[Q] TMO Wi-Fi Calling for UVMC 6 TW
[Q] CM7 and Wi-Fi Calling?
Wi-Fi calling possible on bell sim card? (Using the T-Mobile Wi-Fi calling with cm7)
You can flash TMO Roms on S4 as long as you use KToozens KTweeker kernel you can also flash international ROMs I9505 Roms I prefer these just be sure to flash new kernel before reboot of ROM or it will bootloop / softbrick..
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