Cocotron[1] is a reasonable open source Cocoa implementation. You could very well aim to support both it and Cocoa proper. Beyond UI, I actually have used my O

Cocotron[1] is a reasonable open source Cocoa implementation. You could very well aim to support both it and Cocoa proper. Beyond UI, I actually have used my Objective-C data models from an iOS app on Linux. There is no need for Cocoa there. Objective-C code transitions quite well at that level. That said, I do agree that it is really not a big deal for the vast majority of developers. [1] http://www.cocotron.org http://www.cocotron.org