Hello,
I have run into a situation where a field user needed a shapefile on an offline map which we were not able to add from AGOL as the webmap was created by another and shared with the user, but the reference data contained in the needed shp had not been added in time. The shp was zipped and downloaded to the mobile device, but it appears there is no option to import as a data layer into the Field Maps app directly from the host mobile device. Is there a way to do this? Thanks!