Download of xDiagram 5.7 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This Mac app was originally developed by Vu Tien Thinh. The software lies within Design & Photo Tools, more precisely Viewers & Editors. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe.
From the developer:
xDiagram3 could help you make nice diagram graphic documents quickly by keeping lines connected to shapes even when they’re moved.
The application provides powerful graphic tools for designers, developers to draw UML activity diagram.
You may want to check out more software for Mac, such as 3D Image Commander, UnCoverIt or Ashampoo Cover Studio 2 for Mac, which might be similar to xDiagram.