Night vision in your smartphone. Look at how night vision works.
Do you have a night vision device? No? Then look as you can see with your camera.
The application is created for jokes and practical jokes. Start the application and a green filter will be applied to the image from the camera.
The image will be similar to the image from the night vision device. You will see everything in green tones of night vision camera.
The application is not a replacement device, it's just a joke and a joke that would feel as a special agent with a night vision device.