Spotlight: CF.lumen by Chainfire adapts the colors on your Android device to the sun's position
CF.lumen also works in tandem with your device's built-in light sensor, which it uses to automatically adjust the color according to your present lighting conditions - that's in addition to the sun's position, which isn't always the best determinator for color temperature.
The app provides several color filters to take the eye-straining edge off your display - that's red, green, blue, amber, and salmon. These filters don't merely limit the screen to the respective colors - they convert the image to grayscale first, then that image is shown in levels of the selected color. This way, details that would otherwise be lost are still preserved. CF.lumen also includes grayscale, inverted colors, temperature adjustment, and custom RGB filters - that's right, pick up your favorite color and make it a screen filter.
CF.lumen also has an option for color blindness enhancement, complete with settings for protanopia/anomaly, deuteranopia/anomaly and tritanopia/anomaly. These filters are developed by Google, but Chainfire included them in the app.
Chainfire's screen-comforting app is free, but has an optional paid Pro version, which enables the option to start at device boot and Tasker integration. If you're worrying about performance, the developer says there shouldn't be anything beyond slightly noticeable performance impacts, but it depends on the device being used. CF.lumen doesn't require root, but it runs only on Android 4.4 KitKat and newer versions. As a whole, this is another quality Chainfire production, so treat yourself to it if you wish.