This week, I was exploring the content available on the DStv app on my Samsung NU7100 TV. I noticed that the suggested data usage for streaming in the highest quality, which is 4K, is approximately 10GB per hour. Although I haven't tested this yet, it appears that the DStv app supports 4K streaming on 4K TVs, or at least offers it for select content.
I found this interesting and thought it was worth sharing, especially for those who are concerned about data usage or want to ensure they're getting the best viewing experience possible.