I found what i think is a big clue.. After a few searches on stackoverflow, I found some people having similar issues with the mobile interface on other software. One persons advice was to replace jquery with zepto(a leaner version of jquery).
I replaced the /public_html/imagevue/iv-includes/assets/jquery-mobile/jquery.mobile-1.3.0.min.js
with
/public_html/imagevue/iv-includes/assets/jquery-mobile/zepto.min.js
Now, the thumbs do not display or display in the wrong place. What you see where a thumb should be is the background 'image loading' icon, but tapping it works and brings up the full size image. You can go back and forth with the back buttons(which is what usually fails with the current software after a few tries), and it never fails to recognise the 'tap' or click.. After a little searching I think the issue is something to do with the 'ui-li-thumb' class, but my knowledge of complex javascript is limited so i feel i can go no further.
Is this worth looking into? There must be a lot of users with the same problem. Perhaps you could have brief look at it mjau-mjau?. As you know the code, you might fix it in a jiffy. I do understand that it may not be that easy, but i think the clue i've supplied could help.. i hope so...
You'll see on my attachments. The main menu thumbs all end up in the top left corner
regards,
Jason