The new beta version of acmacOS Catalina can be downloaded using the software update mechanism in System Preferences after installing the appropriate software from the Developer Center.
AcmacOS Catalina 10.15.4 includes communication limits for screen time, a feature introduced for the first time on the iPhone in iOS 13.3 update, and it brings a new accessibility option to the head pointer which allows you to control the cursor with head movements using the Mac camera.
Real-time lyrics are included in macOS 10.15.4, bringing iOS functionality introduced in iOS 13 on the Mac. Live lyrics allow song lyrics to scroll to music in real time so you can follow what is being sung.
References to AMD processors were also discovered in the beta version of macOS 10.15.4, which suggests that Apple is working on AMD Macs, but these references could simply be for internal testing rather than proof of an AMD Mac.
Although not directly linked to “MacOS Catalina” 10.15.4, Apple is adding a new universal purchase option for macOS and iOS applications, which will allow users of Apple devices to purchase an application that works on multiple platforms.