The 1.0.8 version of FltPlan Go for Mac was available to download on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software is included in Lifestyle 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 free Mac application is an intellectual property of Flight Plan LLC.
From the developer:
FltPlan Go is a companion to FltPlan.com, the free flight planning and filing website that covers the U.S., Canada, Mexico, the Caribbean, and Central America. The FltPlan Go Mac desktop app features flight plan filing, airport and FBO information, fuel prices along the route, moving maps, flight tracking, etc.
You may want to check out more Mac applications, such as JMP 7, Spartan or merkaartor, which might be similar to FltPlan Go.