If you’re writing a webapp that watches for “orientationchange” events, you can simulate the event in Safari so you can use the desktop browser’s more advance development and debugging tools.
Use these bookmarklets, or copy/paste the code that follows.
Portrait
window.orientation = 0;
var e = document.createEvent("Events");
e.initEvent("orientationchange",true,true);
window.dispatchEvent(e)
Landscape
window.orientation=90;
var e=document.createEvent("Events");
e.initEvent("orientationchange",true,true);
window.dispatchEvent(e)