For most people looking to take advantage of the cellular benefits of an Apple Watch, the process can be as simple as adding the smartwatch as an additional line to their existing mobile plan. In terms of the price, this will depend on the carrier, although AT&T and Verizon both charge $10 each month for an additional line for a smartwatch. In contrast, a connected device can be set up through T-Mobile (which now includes Sprint) from as little as $5 per month.
Regardless of the purchase price, both cellular versions also require their own line and the cost varies. One of the reasons for this is Apple doesn't charge for cellular access directly. Instead, mobile carriers do with most tending to charge around $10 per smartwatch, per month.
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