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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Schiller on Apple's Yearly Product Timelines
Schiller, however, also admitted that having to come up with a "dazzling" show each January was unsustainable. He also admits that January does not fit into the Apple's natural product timelines, which he specifically spelled out:
He noted that Apple marches to certain annual product cycles: the holiday season (Novemberish), the educational buying season (late summer), the iPod product cycle (October), the iLife development cycle (usually March), the iPhone cycle (June).