Enable Mobile Map Packages to use custom Tile Packages

[LanceCase]

Please enable mobile map packages to use custom, basemap tile packages.  For clarification, basemap tile packages (TPK files) stored outside of the mobile map package (MMPK) in Field Maps.

As of 13Jan25, it looks like feature layers (local or hosted) can be added to mobile map packages which can be hosted in AGO or sideloaded.  However, the mobile map package can only store one imagery layer as a basemap.  We have several basemap raster layers (i.e. NAIP, hillshade, canopy height model, etc.) we use with web maps for Field Maps, which are sideloaded as TPK files.  Most of our AGO storage is static data.  We most frequently collect "waypoints" (points) and "tracklogs" (lines) data that we sync to AGO for use in ArcGIS Pro.  The ability to switch custom basemaps with a mobile map package would allow us to sideload the static vector data rather than store it in AGO.

Thanks!
Lance 

[Debert]

Correct me if I'm wrong, but you can do a raster to VTPK and add that to your MMPK to be used as basemap.

[avillamo]

When I open my map on my iPhone, I can switch between different basemaps that I’ve sideloaded into the same Field Maps folder. I’m not sure if you’ve tried it recently, but I can see all my basemaps stored there and use any of them across all my maps.

What I’d really love is to be able to use an MMPK as a basemap in Field Maps. That would allow me to keep only a few layers in ArcGIS Online for data collection, while each user could create and sideload their own MMPK tailored to their needs. It would make the workflow much more flexible and efficient.