On iPhone and iPad, you can quickly rotate a video stored in Photos with iMovie’s app extension. Many video apps simply don’t offer this option, so it’s nice to have for those quick fixes while browsing videos.
To use this (and most) editing app extensions for Photos:
- In Photos, tap a video to view it full size
- Tap Edit
- Tap the (…) app extension button, usually next to the play button
- In the menu of app extensions that appears, tap iMovie
- (Optional) If iMovie isn’t an option yet in that menu, swipe all the way left, tap More (…), and enable it
- Once the iMovie extension loads with your selected video, place two fingers on the video and twist them left or right
- When you’re happy with your rotated video, tap Done
Credit to Serenity Caldwell for this tip