- Connect iPhone (SE1, iOS 10.2.5) to external monitor via lightning-to-HDMI adapter and HDMI cable. iPhone is now mirroring to external monitor.
- Launch the native Photos app, Camera app, Safari, etc, and see that rotating the iPhone to its side will turn those apps to landscape orientation, and this is properly mirrored on the external monitor.
- Initiate a FaceTime call. The mirror now shows the landscape-proportioned picture rotated 90 degrees counter-clockwise, shrinking the picture and leaving wide spaces of black on the left and right sides.
I've tried swiping and tapping and twirling with my fingertips on the iPhone's FaceTime screen. I've tried toggling orientation lock in Control Center. I've tried app-switching from a landscape app back to FaceTime. I've dug through device Settings (I see no in-app FaceTime settings). I've even poked at my external monitor's controls.
I fear there's no solution, based on the hundreds of replies to this Apple Communities thread over the past three years: https://discussions.apple.com/thread/6650493
And I've of course written to Apple Feedback: https://www.apple.com/feedback/
Anything I've missed?