Original: Official ports are available for some Unix-like platforms, with work-in-progress ports to Classic Mac OS and Mac OS X, and unofficial ports have been contributed to platforms such as Symbian PuTTY for Symbian OS Forum Nokia Wiki - PuTTY for Symbian OS and Windows Mobile.
Simplified: Mac OS and Mac OS X are still being ported, while unofficial ports have been ported it to the Symbian and Windows Mobile operating systems.