Samsung
Turn the Flashlight On or Off auf Samsung
Searching the app drawer for a flashlight app on your Samsung phone will not get you anywhere. Samsung built the torch function directly into the quick settings panel, the same panel that holds toggles for Wi-Fi, Bluetooth, and Do Not Disturb.
To reach it, use this path: Swipe with two fingers to access the Quick settings ➔ Enable or disable Flashlight. A single swipe with one finger from the top of the screen also opens a shortened version of the panel, but the flashlight tile is easier to find once you expand the full view.
Tap the flashlight icon once to turn the torch on. Tap it again to switch it off. There is no brightness slider or separate control, the toggle only supports on and off.
If the tile is missing, it was likely removed during a layout change. Open the quick settings editor, usually reached through a pencil or menu icon inside the expanded panel, and drag the flashlight tile back into the active row.
Leaving the torch on for long stretches drains the battery faster than normal use, since it drives the camera LED at full output. On most Samsung phones the flashlight also switches off automatically the moment the screen locks, so it will not stay lit in your pocket.