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Sweet stuff. I don't know why but I really fancy the idea of wifi calling and essentially never needing to use a cell tower. I hope I can just keep my iPhone in airplane mode from now and just wifi for everything.

Airplane mode disables wifi as well..
 
It uses minutes on T-Mobile. I realize you're on att, but I don't see why it would be different.

It depends on your plan for T-Mobile. Obviously if you have an unlimited minute plan it doesn't matter. There was also a flat fee you could add to make it not count against your plan minutes.
 
It depends on your plan for T-Mobile. Obviously if you have an unlimited minute plan it doesn't matter. There was also a flat fee you could add to make it not count against your plan minutes.
By "uses" I was merely stating that it shows up as minutes used. Even if you have unlimited is says "xxx out of unlimited". My mother is on our family plan and she calls almost exclusively from wifi at home. She has "used" 780 minutes this month.
 
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