WriteMapper 4 works on macOS and Windows.
macOS Technical Requirements
On macOS, it strictly requires macOS 10.11 (El Capitan) or newer in order to run. Older operating systems are not supported (and do not work).
However, please note that major versions of macOS are generally released once a year, and usually maintained for about three years.
Windows Technical Requirements
On Windows, it strictly requires Windows 7 or newer in order to run. Older operating systems are not supported (and do not work).
However, please note that Microsoft has ended support for Windows 7 and Windows 8.
Using Older Systems
If you're using an older version of operating system not currently supported by Apple or Microsoft, some features may not work. In those cases, do consider upgrading to a newer version of macOS or Windows in order to use WriteMapper's features.