When I bring my site up on the iPhone in portrait mode, it looks perfect. If I rotate it to be landscape, it still looks fine. However, if I try to navigate while I'm in Landscape mode, the remnants of the last page are left on the screen and the new page looks like the Portrait version stuck on top and a black background. Then, when rotating back to Portrait mode the black background stays there while the rest goes back to normal. I've attached screenshots of the Landscape mode.

Try to include following css rules to templates/mobile_iphone/css/custom.css:

body {
  width: 100%;
}
body > * {
  -webkit-backface-visibility: visible;
}

And what is URL of your site?.

The url is cffredco.gosidus.mobi. I tried adding those CSS rules, but that didn't seem to change anything, unfortunately 

Any other ideas? I am at a loss and I was hoping to send this to the client this week.

We cannot reproduce the issue on fresh MJ installation, so most likely it's a conflict with other extension (maybe highslide). We will test your site, hope the issue will be localized and fixed.

Hi there, I just tested your site (3 levels deep) w/ iPhone 4S w/ latest iOS and could not reproduce the problem you mentioned. Do you have the latest iOS version on the device you test?

Yes, I tested on my iPhone 4S with iOS 5.1.1. My colleague also tested it on her iPhone 4 with iOS5- not sure if she's up to date or not.

I'm trying to disable extensions to see if that will help, and then I'm going to update to 1.5.26 to see if that will help.

Upgraded to 1.5.26 and still the same issue. Here is a list of currently enabled plugins. I tried disabling any that I though might have a conflict, but that didn't change anything either.

1               Mobile Joomla! Public system mobilebot 66
2 JCal pro common libraries Public system jcllibraries 37
3 JCal pro reCaptcha plugin   Public jcalpro jclrecaptcha 38
4 Mobile - Simple   Public mobile simple 67
5 Content - mosforme Public content mosforme 40
6 EasyImageCaption Public content easyimagecaption 55
7 Content - AllVideos Reloaded Public content avreloaded 63
8 Editor - No Editor Public editors none 18
9 Editor - TinyMCE Public editors tinymce 19
10 Editor Button - Image Public editors-xtd image 21
11 Editor Button - Pagebreak Public editors-xtd pagebreak 22
12 Editor Button - Readmore Public editors-xtd readmore 23
13 Button - Xmap Link Public editors-xtd xmaplink 59
14 DOCLink Public editors-xtd doclink 58
15 Button - AllVideos Reloaded Public editors-xtd avreloaded 64
16 Mobile - AMDD Public mobile amdd 70
17 Mobile - ScientiaMobile Public mobile scientia 71
18 Mobile Joomla! Ad Remover Public mobile adremover 72
19 Search DOCman   Public search docman.searchbot 57
20 System - Core Design Scriptegrator plugin Public system cdscriptegrator 41
21 System - AllVideos Reloaded Public system avreloaded 65
22 User - Joomla!   Public user joomla 5
23 Authentication - Joomla   Public authentication joomla 1
24 Jom Comment   Public content jom_comment_bot 61
25 DOCman Standard Buttons   Public docman standardbuttons 56
26 Search - Content   Public search content 6
27 System - SEF Public system sef 27
28 Jom Comment Sys Public system jom_commentsys_bot 62
29 Azrul.com System Mambot Public system azrul.system 60
30 Content - Page Navigation   Public content pagenavigation 17
31 Search - Weblinks   Public search weblinks 11
32 System - Debug   Public system debug 28
33 Search - Contacts   Public search contacts 7
34 Content - Rating   Public content vote 13
35 Search - Categories   Public search categories 8
36 Content - Email Cloaking   Public content emailcloak 14
37 Search - Sections   Public search sections 9
38 Content - Load Module   Public content loadmodule 16
39 Search - Newsfeeds   Public search newsfeeds 10
40 System - Remember Me   Public system remember 32
41 Mobile - Forever Public mobile always 68
42 Mobile - Domains Public mobile domains 69
43 JCalPro Latest Events plugin   Public content bot_jcalpro_latest_events 35
44 JCal Pro Search plugin   Public search bot_jcalpro_search 36
45 Content - Pagebreak

I disabled all except for the following, and it's still doing the same thing.

1 Authentication - Joomla   Public authentication joomla 1
2 Content - Pagebreak   Public content pagebreak 12
3 Editor - No Editor   Public editors none 18
4 Editor - TinyMCE   Public editors tinymce 19
5 Editor Button - Image   Public editors-xtd image 21
6 Editor Button - Pagebreak   Public editors-xtd pagebreak 22
7 Editor Button - Readmore   Public editors-xtd readmore 23
8 Button - Xmap Link   Public editors-xtd xmaplink 59
9 DOCLink   Public editors-xtd doclink 58
10 Button - AllVideos Reloaded   Public editors-xtd avreloaded 64
11 Mobile - Simple   Public mobile simple 67
12 Mobile - AMDD   Public mobile amdd 70
13 Mobile - ScientiaMobile   Public mobile scientia 71
14 Mobile Joomla! Ad Remover   Public mobile adremover 72
15 Mobile - Forever   Public mobile always 68
16 Mobile - Domains   Public mobile domains 69
17 Mobile Joomla!   Public system mobilebot 66
18 System - Debug   Public system debug 28
19 System - Remember Me   Public system remember 32
20 User - Joomla!