RCode 3.6 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The actual developer of this software for Mac is Runecats. We recommend checking the downloaded files with any free antivirus. RCode for Mac relates to Developer Tools.
From the developer:
RCode is a lightweight and powerful coding application. RCode supports most top language syntax's supporting: Plain Text, C, C, Objective C, CSS, HTML, JavaScript, JSON, PHP, Ruby, Shell and XML. Also this app has a navigator mode to easily see and switch between your project files.
You may want to check out more Mac applications, such as TopCoder UML Tool, GeoServer or InfoPlistChecker, which might be similar to RCode.