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T-Mobile confirms that you won’t be using minutes with Wi-Fi calling
Basically, any T-Mobile users who use phones that support UMA (Unlicensed Mobile Access) are able to make voice calls via Wi-Fi as long as they remain within range, but prior to this, UMA still ate into your plan’s voice minutes. Nice to know that T-Mobile has changed this policy.
To take advantage of this situation, you will need to purchase one of the Android handsets from T-Mobile that will come with the Smart Wi-Fi app installed. Apart from that, you will need to make sure you are on the an Even More, Even More Plus, or 4G Do More plan. Once you fulfil the above mentioned criteria, then T-Mobile will allow you to add “Free Wi-Fi Calling” as a plan option. Go on and enjoy!