According to this documentation, in the section about using a map package from external storage, I should be able to go into Settings --> Map, and then add/edit the folder for the Map Library. However when I go there, it seems to only be read only. I'm on IOS and I cannot browse or type or anything in the space. It just shows the default path (~/ArcGIS/My Surveys/Maps). I am trying to add a path to a folder where the package is already stored (for Explorer) so that I can use it for offline.