Twilight is described as 'The app filters the blue spectrum on your phone or tablet after sunset and protects your eyes with a red filter. The filter intensity is smoothly adjusted to the sun cycle based on your local sunset and sunrise times' and is a popular color temperature tool in the system & hardware category. There are more than 25 alternatives to Twilight for a variety of platforms, including Windows, Linux, Mac, Android and Wayland apps. The best Twilight alternative is f.lux, which is free. Other great apps like Twilight are Redshift, LightBulb, Solace and Red Moon.
Setting the color temp of the screen really only requires about 40 lines of C (80 or so all inclusive). sct is a crude utility which does roughly that. I’d say exactly that, but some of the calculations aren’t actually exact.
A Python program that calculates ambient brightness and sets screen's correct backlight using a camera.
Small GTK GUI application to set contrast, brightness and gamma for wayland compositors which support the wlr-gamma-control protocol extension. Basically this is the example from here: https://github.com/swaywm/wlroots/blob/master/examples/gamma-control.
Away From Keyboard is an app that reduces eye strain with reminders to take a break.
SunshinePal is your daily sunlight companion designed to help you track your exposure, set healthy goals, and reconnect with nature for better sleep and mood.
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iVisionGuard is a screen distance app for Android. Screen time apps count how long you look at the screen. iVisionGuard checks how close you hold it, and reminds you when it gets too close.
EyeAway is a beautiful, privacy-first macOS app that helps reduce digital eye strain using the proven 20-20-20 rule. Every 20 minutes, look 20 feet away for 20 seconds - your eyes will thank you.
