TopoNavigator 3.9 was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The software lies within Education Tools, more precisely Science Tools. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software. This software is an intellectual property of Anavasi.
From the developer:
The TopoNavigator4Pro special edition is addressed to TopoNavigator4 users who want to create aesthetically integral and easily readable maps of professional quality.
You may want to check out more software, such as Panel, Lasergene or gitoolbox, which might be similar to TopoNavigator.