Yes, for what they're meant to do. Apps and built-in settings like Night Shift, Night Light, and f.lux shift your screen to warmer tones in the evening, which cuts the blue light coming off that device and makes it gentler before bed. They're a genuinely useful, free first step.
Their limit is that they only affect the one screen. They don't touch your room lighting, TV, or other devices, and they don't reduce overall brightness much. For fuller protection, combine a filter app with dim, warm lighting and, if you're on screens late, amber blue-light glasses that block blue light from your whole environment.
