Xtreme now has a new device class called .is-ipad so you can use that to hide them on that device with the rule below in MAin Options > Fonts & Custom > Custom CSS Rule box
.is-ipad .mydiv {display:none;}
I have asked @weaver if that class is available in the device attribute of the show_if / hide_if shortcode, and if not if it could be added.
You cannot increase the threshold of the mobile menu, only decrease it, so you cant force the mobile menu on Ipad on Xtreme for now.
Once the fixed icons are gone, the menu should be fine, if not, we can give you some Custom CSS to make it fit