I’ve been struggling all day with the most random-feeling problem. On single posts/articles in my WordPress theme, the site loads fine on an iPad and then if you “spread” to zoom out, you get this weird margin/centering issue that is shown in the screenshot. Basically, the auto margins are ignored and the whole site is shifted off to the left.
I’m told this doesn’t happen on any of the other pages (such as home or category archive pages), but since I don’t actually own a device myself, I cannot test.
There was an improperly closed div in the but fixing that doesn’t seem to have resolved the problem according to my tester. I also, already re-wrote the markup to more closely mimic that of the other non-problem pages, and removed any tricky absolutely positioning, so I’m pretty much out of ideas as to what else would be causing this.

I just checked it on my iPad 3, and the page seems to be perfectly centered. Even after zooming.