This keeps changing so back to V for the answer.
So my family has 4 devices, only 1 is a smartphone the other 3 are basic feature phones. Our carrier is Verizon and we have unlimited talk and text and 500 MB of data, all shared, except the basic feature phones don't have data. If I got a smartphone to add to the plan would it add any cost even if no data was added to the plan?

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