sdk for os4? , nah same as with morhpos, more less just for experienced users or them who have the hw+os installed..
Well, gcc crosscompilers for OS4 exist for Windows, MacOS and AmigaOS 3.x...
For MorphOS at least you have a crosscompiler for 3.x... (if you run UAE you can compile from Windows) ;-P
Although we need an IDE like Visual* or *Builder for both platforms...
