Apple TV

Many smart TVs allow you to download the Apple TV app. See here:

Apple TV app - Devices - Apple

If the smart TV you purchase doesn't support the Apple TV app, you can purchase an Apple TV or other streaming device that supports the Apple TV app.

IdrisSeabright is correct. However, most Apple TV users prefer using an Apple TV HD or Apple TV 4K rather than using a Smart TV's features. I recently bought a new 4K Smart TV and the first thing I did was to buy an Apple TV 4K, why because the user interface on the Smart TV (a high quality Samsung model) is awful and difficult to navigate. The experience of using an Apple TV is much more intuitive, yes they cost money but it is well spent.

You may benefit by learning about Apple's various TV offerings, it is much more than you likely know about. You can learn about them at www.apple.com/tv

While I don't find it horrible on my Samsung TV, I do prefer the dedicated Apple TV box, in part because there are apps that are available on the Apple TV box that are not available on my Samsung TV, for example, Peacock.

The Apple TV App may be available for download if the specific model of TV supports it.

The Tv App on Samsung TVs is however not a full fledged Apple TV replacement. It is an app with access to the iTunes Store content, Apple TV+ subscription service content, and access to some embedded channels. It does not have access to other Apple TV features such as the Computers App for Home sharing, Apple Music, Home Kit support as a Home Hub etc..., or as mentioned the ability to download other Apps into it.

What you expect from the Apple TV App experience will dictate wether you can simply use the included TV App or may want to purchase the full fledged Apple TV box.

I don't have any issues with Samsung's interface really, but yes, the Apple TV has access to more Apps than Samsung's own App store and its interface is much nicer to use than Samsung's.

Also the subscriptions to the embedded channels in the TV App is a different one than the one you may have for the independent apps and they cannot be used interchangeably. So if you already have a subscription to say CBS all access, you cannot use that within the Tv App, you must download the independent App to the Samsung TV instead.

Good point and thank you for pointing that out!