I am not aware of them mentioning an IOS or any MAC based explorer, and I don't foresee that happening until they are able to go entirely HTML5 for ALM. As it is now the alm explorer add-in still needs the underlying Active X controls (it just gets around the signing and limitations but still uses the framework). Microsoft will not license the rights to Active X to anyone at this time, so that is the limitation on a full explorer being offered for other platforms and limiting it to their own Windows product environment. There is limited support and functionality in anything non windows based (safari, chrome, IOS devices, etc). There was an application a couple of years ago for IOS that allowed very limited functionality but it has since been removed from availability (I know as I had it and it was removed from my App purchases, the app store, and eventually my devices).
Unfortunately no such option exists at this time and they don't provide a roadmap of their future development paths for me to say if it will ever be made and made available,