Amazon's line of Firetablets offer a ton of value at budget-friendly price points, and the HD 8, which is perhaps its most popular model, just got a massive discount. The 64GB version is on sale ...
If you're stuck with an older TV lacking smart features, or your existing smart TV isn't compatible with your other stuff, Amazon's lineup of Fire TV sticks is a great (and very cheap) solution.
What is the absolute best tablet you can buy? For all-around quality, the best tablet we've ever tested is the Apple iPad Air, which you can get in its 11-inch size at Amazon for as low as $549.