In the video, a person is holding a phone in front of a car's headlight. The phone screen displays a light meter app, which is used to measure the intensity of the light emitted by the headlight. The person is using the app to test the brightness of the headlight, possibly to ensure that it is functioning properly or to compare its brightness to that of another headlight. The phone is held steady in front of the headlight, and the person appears to be adjusting the angle of the phone to get a better reading. The car is parked in a garage or a similar indoor setting, and the lighting in the room is dim, which makes the headlight appear even brighter.