Download of Safecast 1.00 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.
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. The program belongs to Design & Photo Tools. This free Mac app is a product of Safecast / Momoko Ito Foundation.
From the developer:
Safecast is a radiation measurements tool for Mac. Visualization tools allow you to change map backgrounds and coloring to enhance contrast between measurements allowing you to create customized views and see best how natural and man-made sources of radioactivity vary around you.
You may want to check out more software for Mac, such as HDR MAX, SingleFramer or Piranesi, which might be similar to Safecast.