Downloading serialSave 1.1 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. The software lies within System Tools, more precisely Device Assistants. The actual developer of this free Mac application is pierdr. We recommend checking the downloaded files with any free antivirus.
From the developer:
serialSave allows you to store locally on your computer incoming messages from microcontrollers like Arduino and RaspberryPi. The text files format includes a timestamp for each serial message (each serial message should have an ending sequence, the letter F).
You may want to check out more software for Mac, such as Macfilink, Missing Sync for Palm Pre or LaCie DVD Update Tool, which might be related to serialSave.