One of the accessibility settings in your iPhone is a mode that changes the colors displayed on your screen to appear readable for the visually impaired.
But it also splashes everything on your screen with Halloween-like colors. It's a neat trick if you want to make your iPhone spooky for Halloween.
Here's how to do it.
Go to Settings.
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Tap General.
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Tap Accessibility.
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Tap the switch for Invert Colors. (You can also simply ask Siri to "invert colors.")
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Boo(m)! Your iPhone is now spooky for Halloween!
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Steve Kovach/Business Insider