Undo, redo, and revert changes

Undo the last action: Tap or two-finger tap the screen. Tap multiple times to undo up to 200 of your recent actions.
Redo the last action: Touch and hold , then tap Redo, or three-finger tap the screen. Repeat that if you'd like to redo more than one action.
Revert changes: Touch and hold , then choose Revert to Original to revert all the changes you've made to a photo in the current and any of the previous editing sessions. You can also touch and hold a photo directly in the Photos browser to choose Revert to Original from the Quick Actions menu.
Cancel changes and quit: If you'd like to quit the photo without saving any of the edits you've made, tap Cancel in the top-left corner of the screen and choose Discard Changes.

Undo the last action: Tap or two-finger tap the screen. Tap multiple times to undo up to 200 of your recent actions.
Redo the last action: Touch and hold then tap Redo, or three-finger tap the screen. Repeat that if you'd like to redo more than one action.
Revert changes: Tap to revert all the changes you've made to a photo in the current and any of the previous editing sessions. You can also touch and hold a photo directly in the Photos browser to choose Revert to Original from the Quick Actions menu.
Cancel changes and quit: If you'd like to quit the photo without saving any of the edits you've made, tap Cancel in the top-left corner of the screen and choose Discard Changes.

Undo the last action: Press Command ⌘ + Z on your keyboard, or choose Edit > Undo from the Edit menu at the top of the screen.
Redo the last action: Press Command ⌘ + Shift ⇧+ Z
Revert changes: Click Revert to Original in the Photomator toolbar. You can also Control-click a photo directly in the Photos browser to choose Revert to Original from the Quick Actions menu.
Cancel changes and quit: If you'd like to quit the photo without saving any of the edits you've made, tap Cancel or in the top-left corner of the screen and choose Discard Changes.