Researchers from Brigham Young University (Utah, USA) tested the Night Shift feature available on iOS to see if it has any impact on sleep quality or not.

Blue light filters have been popular for years, according to SlashGear , where they were once limited to desktop apps and web browser extensions before they started becoming standard on mobile devices. . There are many benefits to using a blue light filter, including reducing eye strain and getting better sleep at night.
But in reality, Apple lists Night Shift as a way to reduce eye strain, not improve sleep. Research by Brigham Young University has further demonstrated the effectiveness of a blue light filter on users’ night sleep.

The study involved three different types of participants: those who used their iPhones at night with the Night Shift feature turned off; those who use it at night with the Night Shift feature turned on and those who don’t use their smartphone before bed.A total of 167 adults between the ages of 18 and 24 were followed by an accelerometer while they slept to track their activity. A phone monitoring app was also used with participants asked to use their phone before bedtime. After looking at data on things like how often they wake up after falling asleep, sleep quality and how long they fall asleep, the study found no difference between the three groups.After dividing the participants into two groups – those who slept less than 6 hours and those who slept 7 hours or more per night – the study found that cell phone use was associated with “little difference” in quality of sleep. Although the group that does not use the phone enjoys “superior sleep quality”, using or not using Night Shift does not affect the sleep results even when the user uses the phone before going to bed.