For me, the layout looks ok on my iPhone. The reason why you can move around the layout is because object 'Image2' is outside the viewport, so this make the page wider than it needs to be.
Also, the filename of this image is empty so it looks like you have accidentally to the page?
That was one of the features I loved in the 90 Second Website Builder.
WYSIWYG Web Builder is 100% incidental. Everything works exactly the same.