Continuity Sketch and Markup are two new Sidecar-related features that allow you remotely draw graphics or annotate documents from any iPad or iPhone capable of running iPadOS 13 or iOS 13, along with any Mac that can support the new macOS Catalina.
For occasions where there's a need to copy text from an iPad browser window to a word processor on a nearby Mac and other similar situations, Apple implemented the Universal Clipboard to make the process as easy as copying and pasting. This AppleInsider guide tells you how to turn on this highly useful Continuity function.
One of the key features of Continuity across Apple devices is Handoff. Handoff allows Apple's first-party apps and any third party developers to send an app's data seamlessly between devices so you can "pick up where you left off."
Made available with iOS 8, Continuity and Handoff on iOS and the Mac enable users to receive SMS messages, phone calls, and more across devices. First in our series of tips, here's how to turn on (or off) phone call forwarding to your Mac and iPad.