Why does Apple's mobile phone come with whitening function?

Why does a smooth camera brighten itself after taking pictures? The reason is that it comes with whitening filter function.

You can adjust the sensitivity and its influence on photography. One is speed. Higher sensitivity can get faster shutter speed and be easier to understand. The second is image quality. The lower the sensitivity, the finer the image quality, the higher the sensitivity and the higher the noise. Generally speaking, it is appropriate to keep the sensitivity below 800.