Highlights include many tools for converting units, a bunch of system integrations for checking things like whether a particular Bluetooth device or Wi-Fi device is connected, and a bunch of features for working with images and lists. The application works for both mobile devices, including the iPhone and iPad, as well as Macs. A few of the actions only work on one or the other but the vast majority work on all devices.
To get started, simply install the application and create a new shortcut. The best way to get a feel for the new abilities is to go to Shortcuts, create a new shortcut, and browse the actions by app. You’ll find everything under “Shortcuts”.
See https://lifehacker.com/tech/actions-app-adds-new-features-to-apple-shortcuts