I liked this app for the cool factor. Use your mobile device as if your had night vision goggles, look into the night and see what you otherwise wouldn’t. Take photos in the dark and see the detail of the whole image.
Like any night vision device it requires some small source of light, Moon, night light, a light source behind the camera perhaps. You have the option of adding the effect to your already saved images on you mobile device. If you would like to control the look of the night vision effect use the slide bar at the bottom of the screen, to add or decrease intensity of the night vision.
I only experimented with this free app a little and had fun, I suggest you try the different intensities of the effect to get the desired look you are trying to achieve. And have fun in the dark.