>It doesn't, but if I GPL my own iOS code, NO ONE will want to use it in an actual shipping iOS app of any significance. I don't see how the proliferation of DRM-ridden iOS apps is a laudable goal for a free software project. If you want, you can sell exceptions to let other people to use your code in their apps. I don't particularly like the practice, but the net harm is much lower than if the program was released under a permissive license.