By default, and as advertised by Apple, a user makes a panoramic image by moving the phone from left to right. Apple denotes this movement with an arrow that directs the user to move the camera to the right.
For reasons of both comfort and practicality, however, it may sometimes be better to move the camera from right to left instead. While this can be crudely done by holding the phone upside-down, Apple built in a better way.
Once you’ve launched the Panorama capture mode (Camera App > Options > Panorama), simply tap once on the right side of the screen to switch the panorama capture direction. You’ll see the arrow flip to the other side of the screen to indicate the new direction of motion. Tap it again on the left side to switch back.
Note, however, that Apple will reset the motion from left to right once the Panorama capture mode is closed, so users will have to reset the motion each time if they prefer right to left.
Thanks, Florian, for the great tip!