Unlike all other browsers, Safari refuse to implement Pointer Events. So you cannot use Pointer Events (easily) in your webapp; you have to polyfill for Safari. That was exactly the situation with IE in the 2000's. Edit: I mean with IE in the 2000s you always had to write exceptional code just for it, because it had this massive presence you could not ignore, and it refused to implement standards.
I didn't say, and didn't mean to imply, that all other browsers already have implemented it. They all, except Safari, have announced plans to implement it. (IE and Edge support it now; FF in two releases... Chrome has announced they will support it, but I don't see it yet on caniuse.com....) Safari, explicitly, has declared they will not.
Edit: http://caniuse.com/#feat=pointer. Only Chrome and Opera don't show it in upcoming releases. Opera presumably will support it the minute Blink does.
