If you're talking about Facebook screen rotation on an iPhone... it is 100% essential when going live. The screen needs to rotate to landscape BEFORE tapping the "go live" button in order to match the camera shooting in landscape... or the video displays sideways, which it most certainly does for me. So, it's a phenomenal suck job that this is happening. I've heard rumors that the feature works on the iPhone Plusses. Don't know for sure. I only have a regular iPhone 8. Oddly, if you tap "go live" first, and then rotate the phone, the live video will display with the correct orientation, however, what you see in the camera's viewfinder is so stretched and distorted, you can't tell what your shooting frame is. Image of that is attached here...