It may be that you notice an icon in the status bar on your Samsung Galaxy S5, which looks like an eye. This symbol appears at regular intervals and then disappears again. If you are wondering what is going on with the eye icon at the status bar, we want to tell you about it. The eye icon comes from the function Smart-Stay which is implemented at the Samsung Galaxy S5. Smart Stay is a function which can illuminate the display as long as you look at it.
This means that whenever the symbol with the eye appears at the top of the screen the Samsung Galaxy S5 checks whether you are watching the display or not. For this purpose, the front camera is used, which checks for simple patterns, whether you're still watching the screen.
If you are bothered of Smart Stay on the Samsung Galaxy S5 and you want don’t want to see an eye icon in the status bar, then you can turn off the function as follows:
Go to Menu -> Settings -> Display
In this sub-menu of your Samsung Galaxy S5 you will find an option called "Stay Smart". Remove the check mark and then the function will be disabled on your Samsung Galaxy S5. The eye icon will not appear anymore at your status bar.