I have sideloaded a tpkx imagery basemap to my iOs devices to the Field Maps folder.
When I create my Offline Area, I use the 'Device will use an installed tile package.' option and put the name of my basemap there.
Once I download the Offline Area in Field Maps, it displays with the side loaded basemap turned on. However, if I select the Default basemap (the one included in the offline area from the web map), it selects/highlights the Default basemap icon, but doesn't change the map. Only the sideloaded basemap is visible, and is not possible to turn off.
Is this a bug or by design? If by design, then why even show the "Default" basemap along with the sideloaded one in the Basemaps window if you are forced to only use the sideloaded one?
As a workaround, since we don't always want imagery in the background, if you enter the "wrong" filename for the basemap in the Offline Area (or rename the local basemap to something else), it will warn you when you download the area that the "Local Basemap Not Available", then select "Continue"
Now, it will still see the downloaded Basemap (even though it is spelled wrong) but, you now have the option to toggle between the Default and the sideloaded basemap.
R_