Iris Mini Pro is software for eye protection. It can reduce the color temperature of the screen and it can also reduce the screen brightness without increasing the flicker rate of the monitor (the so called PWM problem).
Think of color temperature like decreasing the blue light emmited from the screen. At night the blue light stops the secretion of melatonin, the hormone responsible for our sleep. What Iris does at night is based on your location it makes your screen a little more yellow or red depending on the value of the color temperature. This is like other softwares like f.lux, Night Shift and other blue light blocking softwares.
The other cool thing is about the brightness. When your monitor is working it flickers all the time. This flicker is usually at really high frequency and we don’t detect it. There is no way to make monitor without this flicker and this is not the actual problem. The problem is that most monitor makers control the brightness with decreasing this flicker rate (the so called Pulse Width Modulation). And the lower the frequency the worse for our eyes. This is the reason you feel eye pain, headaches and other problems from the PC. Well Iris mini can change the brightness without decreasing the flicker frequency which is really cool.