Apple gave us the ability to invert colors on the screen a very long time ago. Then they gave us grayscale mode in iOS 8, Night Shift in iOS 9, and the red screen filter in iOS 10. The new iOS 11 was supposed to integrate the long-awaited Dark Mode that we've all been wanting. Did it? Well, sorta.
While it's not exactly the Dark Mode we wanted, there's now an option in iOS 11 to enable "Smart Invert" which reverses the colors of the iPhone's display, just like the "Classic Invert" did for all these years. But this special new inverted mode won't reverse everything. Specifically, it won't reverse images, media, and some apps that use dark color styles already, to quote the settings.
To access this new inverted mode, head to Settings -> General -> Accessibility -> Display Accommodations, then toggle on "Smart Invert" from the menu. That's it.
The differences between Smart and Classic Invert are small. For instance, the Maps app looks exactly the same with both, while the home screen with Smart Invert enabled looks the same as without any inverted look on.
In the Photos app, you can see that the UI turned black in both cases, but Smart Invert did not mess with the images or videos at all, which makes it way more useful for those of us yearning for a real Dark Mode in iOS 11.
If you really like this new Smart Invert option, you're like to be turning it on and off quite a bit. If that's the case, you'll want to set up an Accessibility Shortcut. You can do this using either the triple-click home button shortcut or by adding the Accessibility Shortcuts icon to the Control Center.
Either way, whether you're doing the triple-click shortcut or the Control Center shortcut, you'll need to go to Settings -> General -> Accessibility -> Accessibility Shortcut, then just select Smart Invert Colors. Now, whenever you triple-click the home button, you'll get a menu to toggle on Smart Invert from, as you can see below.
To use the Control Center shortcut, go to Settings -> Control Center, then add the Accessibility Shortcuts control to the "Include" list. Then just long press or 3D Touch on the icon in the Control Center to bring up the menu where you can toggle Smart Invert on and off.
Hopefully, this is just the precursor to the real Dark Mode that'll appear on the iPhone X since it will ship with an OLED display instead of Apple's standard LCD one.