Does this happen in low light situations? If so, it's just the way cameras work. Especially cameras on phones. They don't have big lenses, so they can't gather a lot of light. The result is a lot of noise in low light situations. It's just the camera attempting to decipher what it can't interpret. It happens on all cameras. Noise looks like snow or graininess. It shouldn't be a problem with your screen or your camera, it's just the way all cameras work, even really expensive ones.
