A Blue light filter decreases the amount of blue light displayed on the screen of the device. Blue light can suppress the production of melatonin (sleep-inducing hormone), so filtering it out can help you sleep better. It will also reduce digital eye strain, so your eyes won’t feel so tired by the end of the day.
How to install.
1. Open Terminal Emulator
2. sudo add-apt-repository ppa:nathan-renniewaldock/flux
3. sudo apt-get update
4. sudo apt-get install fluxgui