iOS and landscape video

There’s simply no way around it — actually watching video using Apple’s native TV app is just an appalling user experience. Here’s how it works: if you’re watching a video on the TV app — presumably, one that you bought or rented on iTunes, streamed through one of Apple’s native partner channels, like HBO or Showtime, or whatever the method for using Apple TV Plus will be — on an iOS device, it will play in portrait. It also looks terrible.

The Verge

I agree that I find a lot more iOS video apps, especially Apple's default to portrait video when the phone is rotation locked.