Unlike an Android smartphone, it's a little more complicated to enable or disable the display's automatic brightness on an Apple iPhone with iOS 12.
If you are looking for the corresponding option under iOS 12 on your iPhone or iPad, these instructions are intended to support you:
Activate or deactivate Auto Brightness
1. Opens the settings on the iPhone
2. Navigate to "General" and then to "Operating Aids"
3. Tap "Display Adjustments" on
4. Activates or deactivates "Auto Brightness"
Here, your iPhone will now automatically adjust the screen brightness, depending on the ambient light. However, you can still adjust the brightness via the Control Center.
Adjust brightness - iPhone
To do this, move once from bottom to top to the center of the display - the Control Center opens.
You will see the brightness bar. Drag it upwards to brighten up the screen. Drag the brightness bar downwards to reduce the brightness.
You now know how to activate automatic brightness on an iPhone or iPad.