One of the defining features of the new macOS update is the splitting up of iTunes. What was once one app is now divided into Apple Music, Apple TV and Podcasts. Syncing with iOS devices is now also handled by the Finder instead.
Another key feature of the new macOS is the Sidecar. It basically allows iPads to be used as a second screen for Macs. Best of all, the feature can be used both wirelessly or with a wired connection. To get macOS Catalina, head to system preferences and select software update. From the looks of it, there’s plenty of reason to do so as soon as possible. (Source: Apple, The Verge [1], [2])