In order to hide the navigation bar when a page first presents in the iPhone, I put this code in the html of the mobile_iphone template at the end before the end html statement. The effect is the page is presented at 0,0 and the navigation bar scrolls up under the Apple iPhone header after the page completes loading. This gives more realestate. The navigation bar is still there, the user just needs to move the page down to see it. This does not erase the page position value though if the user switches between pages. It seems to just affect the first time a page is presented. I noticed Google does this for their iPhone display. Not sure where this belongs. It could be a iPhone set-up switch or could be added to the mobileJoomla template at downloading as a comment or remain tribal knowledge in the forum.
<script type="application/x-javascript">window.scrollTo(0,0)</script>
<script type="application/x-javascript">window.scrollTo(0,0)</script>