Webmaps containing WMTS basemaps from the OS Maps API fail to load in ArcGIS Field Maps on Android if the service has an access key and was first added as a Content item before being added to the web map.

Workaround

1.Instead of adding the WMTS as an AGOL content item first, add it directly into Map Viewer when creating a new map using ‘Add layer from URL’.

2.Add the URL in the same way as before, appending the custom parameter key.

3.ArcGIS Field Maps on Android will open this web map without error.

Steps to Reproduce