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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Apple Releases First Beta of iOS 13.1 to Developers
Developers who have downloaded the profile for iOS 13 from the developer website will receive the iOS 13.1 beta over the air.
Apple has never before released a point update to an iOS beta ahead of when a new update has launched, so it's not clear if this release of iOS 13.1 is a mistake, or what might specifically be included in the update. While it was originally believed the iOS 13.1 beta was an error, it appears that Apple is indeed testing an iOS 13.1 update that will be released shortly after iOS 13.
The iOS 13.1 release notes suggest that the update reintroduces the Automations feature in Shortcuts, and adds other functions that were removed over the course of the iOS 13 beta testing period.
Apple has seeded eight betas of iOS 13 so far, with the last one having been released on August 21. iOS 13 is expected to be released in September alongside new iPhones.