gnustep

You wouldn't believe the opportunity and cost savings, image overhaul companies miss when they don't do the scheme below:

1) port to gnustep/linux

2) cleanup and get rid of accidental Linuxisms compiling for freebsd

3) spare a week for osx port, yes once you start with gnustep, not the cocoa, it is damn easy. There are apps you can compile from single source resulting in osx and Linux binary.

Once you do these, ios and android is there, waiting for you. Once you get a mobile interface of course.