Yes, you can use the Apple TV 4K (3rd generation) even if you don't subscribe to an Apple TV+ streaming service. Here are some ways you can use the Apple TV 4K without Apple TV+:

- Rent or buy films and series: You can rent or buy movies and series from the iTunes Store and watch them directly on your Apple TV 4K.
- Other streaming services: You can also use other streaming services such as Netflix, Prime Video, Disney+, Hulu, YouTube TV and many more as they are available on the Apple TV 4K.
- Apple Music and Apple Arcade: You can also use Apple Music and Apple Arcade to listen to music or play games.
- Smart Home Hub: The Apple TV 4K can also act as a smart home hub to control your smart home devices.
- Photos and other Apple services: You can also view your photos and other content from your Apple devices on the Apple TV 4K.

The Apple TV 4K therefore offers a wide range of possible uses, even without the Apple TV+ streaming service.