Yes, it is possible to have multiple basemaps in a Collector for ArcGIS map for offline use. In some instances, using the same data for different visual representations may require the use of different basemaps in a map that is made available offline. To add multiple basemaps, refer to the following workflow that uses a World Imagery basemap as an example.
- Navigate to the World Imagery (for Export) page for the basemap and scroll down.
- On the right pane, under URL, click the Copy button to copy the service URL.
- In ArcGIS Online, navigate to Content > Add Item > From the web.
- Paste the URL copied in Step 2 and provide the necessary ArcGIS Online credentials. When prompted, opting to save the credentials prevents the sign in dialog from appearing when the item is accessed.
- Add the world imagery layer to the web map and click Save.
Repeat Steps 1 through 5 to add another basemap.
- Open Collector for ArcGIS and download the map.
- The option to turn the additional basemap on or off is now available in the Layers menu.