I have T-Mobile One + 55 that allows me unlimited data in 210 countries outside the US. If while in one of the covered countries I use my phone as a personal Wi-Fi hotspot ( I assume I can do that since I have unlimited data), will my wife be able to connect to my Wi-Fi hotspot and thus make free Wi-fi calls to the US without incurring additional charges? The T-Mobile website offers conflicting information regarding this. On one hand it says wifi calls are free but it also says that international wifi calls to the US are $.25/minute. One other question: If the calls made on my wife's phone while connected to my personal wifi hotspot are free, will my phone (the one with the wifi hotspot) be charged for the calls made on my wife's phone while connected to my personal wifi hotspot?
From what I'm seeing, you'll need the On Demand Data Passes and a 3G/4G data connection in order to use your device as a hotspot. In this case, you'd be charged for the data feature needed to use the service on your hotspot phone.
I suggest you use a VoIP app, such as Skype, Viber of Hangouts.
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