A year ago, after 2 years working all day in front of 3 monitors and having used computers for most of my lifetime I hit a point where after about 3pm I struggled to read on my computer. A little before that I had heard about screen glasses, so I ordered a pair and the problem went away. I now wear them whenever I am using a computer and frequently when using my phone.
I will not go into a lot of detail, but our eyes were not designed to stare at a light source all the time. Most of the light we are naturally exposed to is reflected, so when we stare at screens that are emitting light all day it is unsurprising if our eyes do not do well. Screen glasses block some of the UV light and blue light emitted by your computer screen (without drastically altering the colors you see on screen), which helps eyes cope with staring at a screen all day.
I have used and like screen glasses from three different companies:
Izipizi - They are the cheapest, but incredibly comfortable, look good and are available with reading glasses magnification.
Felix Gray - The most expensive, but have frames similar to what you would find at warby parker.
Pixel - In between in terms of price. The yellow tint of the lenses is more noticeable.
Gunnar also sells screen glasses. I have not tried these and the yellow of the lenses is very apparent.
If you already wear prescription glasses It is also possible to get a coating put on them that blocks UV and blue light just like screen glasses do.
I recommend whichever brand sells a pair of screen glasses that you do not mind, or even enjoy being seen in. Each of the brands I have tried has helped me look at screens as much as I need to working at a minimum 8 hours a day in front of 3 monitors plus all the other time I spend on my phone, personal computer and watching television.
As a side note Warby Parker is missing a huge opportunity here. Young professionals make up a large portion of their customer base. They could all use screen glasses and they already like Warby Parker frames. Some of them so much so that they are already wearing Warby glasses without a prescription.