Anybody who has spent late nights up on their PC or notebook is well aware that it has a negative effect on vision and quality of sleep. More recently, blue light has been identified as the cause of this issue, prompting Apple to launch a Night Shift feature on some of its mobile devices (the 9.7" iPad Pro). This feature is now set to land on macOS notebooks via the latest update for the OS X Sierra beta (10.12.4). 

For those unfamiliar with Night Shift, it adds a yellow hue to the screen, in order to limit the amount of blue light. Whether or not it will improve the quality of viewing on Mac's late at night remains to be seen, but it certainly has lessened the strain on our eyes while using iPhones and iPads. 

The current iteration of Sierra is 10.12.3, with no indication from Apple when the next update will arrive. Is is, however, expected to be available alongside the 10.3 update for iOS.