How to watch anything 4K on Sony s XBR-65X900A?

I m not sure how to watch anything 4K on this TV. The youtube app and Netflix app doesn t appear to play 4k content on the TV. Im not sure how to get 4k content from my gopro hero4 on the TV either.

Read more: How to watch anything 4K on Sony s XBR-65X900A?