How Do I Get My iPhone Out of Negative?

To make the iPhone more accessible, Apple created an inverted color scheme for its devices, including the iPhone. This feature, known as White on Black, makes the background black and the font white. For some users, this level of contrast is easier to read. If you want to turn it off, however, you can easily do so directly on your iPhone.

...
The iPhone offers many accessibility features.

Step

Navigate to the iPhone's home screen.

Step

Tap the "Settings" app, which looks like a picture of silver gears.

Step

Tap "General."

Step

Tap "Accessibility."

Step

Slide the toggle switch next to "White on Black" to "Off."