Download of K3NetServer 1.1 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. The program is categorized as System Tools. The unique ID for this application's bundle is com.ks7dSoftware.K3NetServer.
K3NetServer was developed to work on Mac OS X 10.6 or later. We recommend checking the downloaded files with any free antivirus. This free software for Mac OS X was originally created by Mike Downs, ks7d. The most popular version among K3NetServer for Mac users is 1.1.
From the developer:
K3NetServer is a free Mac OS X app that provides a communication link between an iDevice app via WiFi and an Elecraft K3 radio via usb/serial port. Specifically, this program is designed to work with the K3iNetwork app to allow remote control of the K3 from the user's iPhone, iPad, or iPod Touch.
You may want to check out more software for Mac, such as iStar Composer, SpaceReporter or Matchprint Virtual, which might be similar to K3NetServer.