Download of GraTeX 1.0 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. The application lies within Education Tools, more precisely Science. 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. This free Mac app is a product of Lukasz Opiola.
From the developer:
GraTeX is a Java application for creating graphs. The program lets you design and edit vertices, edges, and labels to your liking thanks to a wide range of variants adequate to the TikZ library. GraTeX incorporates common editing mechanisms like saving/loading projects, undo-redo anf copy-paste operations, and many other useful features.
You may want to check out more software for Mac, such as Genealogy Pro, sciatrope or Curvus Pro X, which might be similar to GraTeX.