Once you signup on Amazon website you can use Sling TV on any of their supported devices.
Details from Amazon site:
You can sign up for Sling TV and get this deal on Amazons Website.
*2 months for the price of 1: Available to new customers upon account activation. One per customer and cannot be combined. Must provide email address and credit card. Must pre-pay to receive second month free. The number of devices that may be allowed to watch simultaneously will depend on the Service you select. Certain channels are limited to watching on one device at a time (single stream), while others allow for up to three devices watching simultaneously (multi-stream). Channel availability may vary based upon geographic location. Certain programs may be unavailable due to programmer restrictions or blackouts. Only available within the United States. State and local taxes apply. All prices, fees, charges, services, programming, features, functionality and offers subject to change without notice.
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