There are four major platforms: Roku, Fire TV, Apple TV, Android/Google TV.
All advertise content in one way or another. Amazon's Fire TV interface has the most separate ads. Android/Google TV has the next most ads in the interface, followed by Roku. Apple TV has the fewest (none), however, Apple TV does as Amazon and Android/Google do with highlighting content within other content listings. It's more subtle, but it's advertising their content. Roku doesn't. Ads for content/apps are easily identifiable as such.
Now, within the content itself, you'll find ads on many free services. That's the way those free services -- Roku Channel, Pluto TV, Xumo, Tubi, Redbox, IMDB, and all the others -- make money. This is true regardless of platform. Turning off the ads is a violation of the Terms of Service to which you agreed.
Roku Community Streaming Expert
Note: I am not a Roku employee.
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