SimpleDemViewer 7.5.6 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. This free software for Mac OS X was originally designed by Yoshiaki Katayanagi. We recommend checking the downloaded files with any free antivirus. The software is included in Education Tools.
From the developer:
SimpleDEMViewer browses DEM (Digital Elevation Model) data as pictures. It displays color elevation maps with shading. It supports gtopo30, etopo2, etopo5, globe, srtm, srtm dted, hydro1k, and many bil form data. User should prepare DEM data separately. You can make Mercator projection map, Corn projection map, orthographic projection maps. You can show pictures, movies or Web pages linked to any places on the earth using memo function.
You may want to check out more Mac applications, such as Calcline, Xfoil or Schematics Plus, which might be similar to SimpleDemViewer.