Download of Mac Grayliner 2.2 was on 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 lies within Education Tools, more precisely General. This software for Mac OS X is a product of Black Cat Systems.
From the developer:
Mac Grayliner displays a map of the entire Earth, showing day, night, and more importantly, the terminator between day and night. Studies have shown that enhanced radio propagation occurs between two points which are both on the day/night terminator.
You may want to check out more software for Mac, such as RUMped, which might be related to Mac Grayliner.
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