Drop down menu makes content invisible


I have an app that uses a dropdown menu to select a device. I am experiencing a scenario only on Iphones, where when the dropdown menu is accessed after a certain set of conditions the content on the page is all made invisible, if you know where the items on the page are they will interact, but they cannot be seen. I have a feeling this has something to do with the nature of how the dropdown menu appears on an iphone vs an ipad or an android device, but do not have the slightest idea of where to look to begin debugging this.