In his popular book The Circadian Code, Satchin Panda explains through rigorous scientific argumentation the impact of light on our sleep and health. One key idea from his work is that technology has messed up our circadian code by disrupting our normal sleep and waking time. The same argument is echoed in Matthew’s book Why We Sleep. The time we spend at night in front of our devices particularly the last two to three hours before bed significantly impact the quality of our night sleep, that is, our REM or deep sleep. The blue light coming out of our mobile devices, the authors contend, is criminally responsible for the disruption of our sleep by ticking our brain to delay the release of sleep hormone melatonin.
However, if you are like me and can not go without technology before bed then you can use some tools to help mitigate the damage. These are tools that dim the screen of your devices and help you reduce potential eye strain. Flux which I reviewed a few days ago is one of them. However, iOS devices has a night shift feature which does almost the same. It “automatically adjusts the colors of your display to the warmer end of the spectrum—making the display easier on your eyes.” Here is how to turn it on on your iPhone:
There are two ways to turn Night Shift on and off:
1- Open Control Center. Firmly press the Brightness control icon, then tap 
to turn Night Shift on or off.
Go to Settings > Display & Brightness > Night Shift.
2- On the same screen, you can schedule a time for Night Shift to turn on automatically and adjust color temperature.
By default, Night Shift turns on from sunset to sunrise.
