resize-se.js

	var resizeHandle = document.getElementById('resize-se');

	resizeHandle.addEventListener('mousedown', function (e){
		var isDragging = true;
		var mousePosition = {x:event.clientX, y:event.clientY};

		document.addEventListener('mousemove', drag, false);
		document.addEventListener('mouseup', function (e){
			document.removeEventListener('mousemove', drag, false);
			document.removeEventListener('mouseup', arguments.callee, false);
		}, false);


		function drag(event) {
            // console.log("firing drag", event.clientX, event.clientY);
			var wnd = Titanium.UI.currentWindow;
			wnd.setBounds({'x':wnd.getX(), 'y':wnd.getY(), 'width':event.clientX, 'height':event.clientY});
            Spaz.Windows.onWindowResize();
	        return;
		}
        event.stopPropagation();
	}, false);

Do you find this is laggy? All my experiments show updating the window size is slow

I do find it laggy (see my comment on the issue in lighthouse). Really hoping they can patch it up somehow to work better. I don't know of a better approach though.

Well your code its virtually the same as mine, so i think this is the best solution for now. Cheers