On the Rotate tab, turn on Check New Photos Overnight. Allow notifications when asked, so Photo Tidy(er) can tell you what it finds.
How it works
While your iPhone charges overnight, iOS gives Photo Tidy(er) time to check new photos: ones added since the last check, and ones taken in the past day. It looks for sideways photos the same way a scan does, on your iPhone.
If any need fixing, a notification arrives in the morning, like “4 sideways photos from yesterday. Tap to review.” Tap it to open the review. What it found also waits at the top of the Rotate tab, with a Review button.
Nothing is fixed overnight. You review and fix the suggestions as usual. See Reviewing suggestions.
Under the switch, Last checked says when it last ran.
When it doesn’t run
iOS decides when background work runs, so some nights a check may be late or not run at all. It only runs while your iPhone is charging.
What it skips
Like a scan, it skips screenshots, videos, photos you’ve already reviewed, and photos that aren’t on your iPhone. It checks up to 500 new photos a night, newest first. After a big import, scan for the rest on the Rotate tab.