The 3.1 version of JMRI for Mac is available as a free download on our website. The following version: 2.1 is the most frequently downloaded one by the program users. This Mac download was scanned by our built-in antivirus and was rated as malware free. JMRI.2.12.dmg is the most frequent filename for this program's installer. The software lies within Design & Photo Tools, more precisely 3D Modeling. This free Mac application is an intellectual property of jmri.
From the developer:
This applications is made by some tools for model railroad computer control.
You may want to check out more software for Mac, such as DecoderPro, which might be related to JMRI.