[A930Rocket]

If you go to accessibility shortcut, you can set it for a red screen or invert the colors with three clicks of the home button. The inverted color isn’t perfect like a dark skin but is similar.

Edit...screen capture doesn’t work with the red or inverted colors.

https://ios.gadgethacks.com/how-to/keep-your-night-vision-sharp-with-iphones-hidden-red-screen-0173903/