This is an excellent question & we're so glad that you have reached out to us. Making sure you have you know how much data something uses is important. When you are not connected to wifi & using FaceTime, you will be using your data allowance. There's a great tool that you can use called the Data Calculator & this will help you with measuring your data usage. Please click here http://vz.to/1KfMGON to start using the Data Calculator.
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