This section gives you step by step instructions on how to invert the display colours in iOS 15, with pictures of the screens to help.
1. Tap the Settings icon on your Home screen to open the Settings app. Scroll down and tap Accessibility.
2. On the Accessibility screen, tap Display & Text Size.
3. On the Display & Text Size screen tap the toggle switch for either Smart Invert or Classic Invert. Smart Invert inverts the display colours, but photos and media remain unchanged. Classic Invert inverts everything.
4. When you are happy with your settings, you can return to the Home screen by swiping up from the bottom of the screen or by pressing the Home button on devices with a physical Home button.