Use your smartphone as a flashlight
Just tap the button in Bright Light Torch and your smartphone's flash will automatically turn on so you can use it to light up whatever you need. To turn it off, all you have to do is tap the same button again.
This app also includes a few different tools that might be useful from time to time; there's a compass on the top of the screen, and a level at the bottom, so you can measure the inclination of any object. Bright Light Torch is definitely a great and useful app for lighting up dark rooms or figuring out which direction is north, among other things.