Can I show a portrait desktop on a rotated AirPlay TV?

Yes, when the TV is connected to the Mac as an AirPlay display, you can stream a portrait virtual desktop to it and rotate the streamed image. This requires Pro streaming features and macOS Screen Recording permission.

1. Create and connect a virtual screen with a portrait aspect ratio such as 9:16.
2. Connect the TV through AirPlay as an extended display and confirm that it appears on the Mac.
3. In the virtual screen’s app-menu section, open its streaming menu and select the AirPlay TV as the target.
4. Open the stream’s video adjustments and use Rotate to choose 90° or 270°, matching the TV’s physical orientation. Adjust the image’s size and alignment as needed.

Keep the content you want to present on the virtual desktop. The virtual screen is the source. The connected TV receives its rotated image. BetterDisplay does not itself establish the AirPlay connection or turn an unsupported receiver into an AirPlay display.

If you want the stream window to remain visible when the Mac locks, enable Show on Lock Screen in the stream’s menu. This option is available in the ordinary overlay presentation, with Full Screen Window Mode off. Also check that the virtual screen is not set to disconnect on lock under Advanced Virtual Screen Settings….

Lock-screen visibility does not keep the Mac awake or guarantee that AirPlay and capture continue through lock, logout or sleep. Test those transitions before using the setup for unattended signage. See Streaming for capture, transforms and reconnection options.