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.
macOS Catalina Now Available
iTunes For Windows is Sticking Around
Apple told Ars Technica that on Windows, there will be no changes. Those who use iTunes on a PC to manage their devices, listen to music, and make iTunes purchases will be able to continue to do so.
There were no details provided, however, on what's going to happen when the Music, Podcasts, and TV apps gain new features over time. Whether those features will also come to iTunes on Windows remains to be seen.
For now, though, Windows users will see no changes to iTunes on the Windows platform.
As for Mac users, installing Catalina removes iTunes and replaces it with Music and Podcasts (TV is coming this fall). Device management is still present in macOS Catalina, and you'll see an iPhone or an iPad plugged into your Mac listed as a device in the Finder sidebar.