If you’re reading this, it’s because you’re staring at a computer screen that’s constantly emitting blue light, the light from your computer screen that blocks your body’s melatonin secretion and, as a result, interrupts your circadian rhythm. We know that staring at electronic devices for long periods of time can be dangerous for our health, but when your job forces you to stare at a computer all day (or your moonlighting freelance gig has you up in the middle of the night), it’s really difficult to find a way to reconcile health and productivity. There’s no easy solution for this one, but if you have to stare at a screen when you work, here are four apps that could help reduce eyestrain, a problem for as much as 61% of US adults, and keep you working.