Is it possible to have multiple basemaps in a Collector for ArcGIS map for offline use?

Answer

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.

1. Navigate to the World Imagery (for Export) page for the basemap and scroll down.
2. On the right pane, under URL, click the Copy button to copy the service URL.

3. In ArcGIS Online, navigate to Content > Add Item > From the web.
4. 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.

5. Add the world imagery layer to the web map and click Save.

Note:
Repeat Steps 1 through 5 to add another basemap.

6. Open Collector for ArcGIS and download the map.
7. The option to turn the additional basemap on or off is now available in the Layers menu.