XmlSpy 1.0 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. We recommend checking the downloaded files with any free antivirus. This free Mac app was originally designed by WuYang Deng. The application is categorized as Developer Tools.
From the developer:
XMLSpy is an application that lets you view the content of XML/HTML/XSL files in a tree outline view and search for keywords rapidly. This is a small but useful tool to check your XML file(s). The free edition cannot modify the source of the XML/HTML/XSL file.
You may want to check out more Mac applications, such as MacCVSClient X, AcidSearch Installer or AlbumEnabler, which might be similar to XmlSpy.