Night Mode Enabler
Want access to the Night Mode Quick Tile on Nougat? Seems like it's hidden. But with this amazing app, you can get a sweet VIP pass to that awesome blue-light killer.
If you're having trouble - make sure to click "On" in the top left rather than the switch in the top right once it opens System UI Tuner.
Note: On Android 7.1 and higher - this feature is officially built into the operating system, called Night Light. However, this feature requires a driver, and as a result, only is available on Pixel and Pixel XL (and newer devices). As a result this will not work on Nexus devices on that version.