Flux is a small programme that avoids that glare that you get when looking at a screen. It’s particularly effective when using a screen later at night.
It’s a free program to download for both Mac and PC. I’ve installed it on around 30-40 machines, and had overwhelmingly positive feedback from a lot of people struggling with the glare and bright light emitted from screen time. It’s a relatively small program but it is packed with features, check out the fluxometer on their website.