I think he's trying to say that Apple don't view it as a zero sum game in that they either get ios developers or some other platform does. By promoting HTML5 e

I think he's trying to say that Apple don't view it as a zero sum game in that they either get ios developers or some other platform does. By promoting HTML5 everyone gets those developers, including them, and so if everyone developers in html5 they essentially have all the competition plus who ever is natively developing, so they have access to a host of programs that might otherwise only be available on competing platforms.