I am a Water and Sewer Utility Director, and have created a water and sewer map in ArcMap 10.3.1. I recently upgraded to ArcPro so I could upload my map to ArcOnline. The problem I am finding out is that the basemap I used to create my initial map is an .ecw file, provided by my local GIS authority. What do I need to do with that file in order to make it a basemap on ArcOnline, to be viewed in the Explorer for ArcGIS application on a tablet.
Thomas Township Department of Public Works