Night mode is an automatic setting which takes advantage of the new wide-angle camera that's in the iPhone 11 and 11 Pro models. It's equipped with a larger sensor that is able to let in more light, allowing for brighter photos when the light is low.
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More Purported iTunes 9 Screenshots Surface [Updated]
MacRumors has been unable to confirm the authenticity of the supposed screenshots, but the same source has now provided additional screenshots to Boy Genius Report, revealing an iTunes version number of "9.0b15 (12)".
Image from Boy Genius Report
Image submitted to MacRumors
Update: We have good reason to believe these screenshots are fake.