Set the amount of time that elapses before the Samsung Galaxy S9 times out and shuts off the screen with these steps.
Set Screen Timeout
- From the Home screen, select “Settings” > “Display” > “Screen timeout“.
- Choose one of the following:
- 15 seconds
- 30 seconds
- 1 minute
- 2 minutes
- 5 minutes
- 10 minutes
Enable or Disable “Smart Stay”
The Galaxy S9 has a feature that will detect if your eyes are looking at the screen. If your eyes are detected, the screen will not time out. Enable or disable this setting with these steps.
- From Home, select “Settings“.
- Choose “Display“.
- Set “Smart stay” to “On” or “Off” as desired.
Disable Screen Timeout
The Galaxy S9 does not have an option to completely disable the screen from timing out when the phone is not plugged in. You can however set the phone to never disable the screen when it is plugged in using these steps.
- Select “Settings” > “About phone“.
- Tap “Build number” 7 times to unlock developer mode.
- Now under “Settings” you have an option for “Developer options“. Under this menu, there is a “Stay awake” option.