macOS Catalina allows you to take advantage of the iPhone and iPad to frimare the documents in Preview, and Quick Lock directly on Mac. Taking advantage of macOS Catalina, iOS 13, and/or iPadOS, we can then create a digital signature for PDF and other documents using the touch screen of the iPhone and iPd. In the new app Preview on macOS Catalina, you can just open a document and go to Tools > Annotate > Signature > Manage [...]

Link to the original article: How to sign a document on macOS with iPhone and iPad