Collector for ArcGIS should have a legend for non-editable (reference) layers in the map.
I completely agree. My group would like to use reference layers like NOAA weather watches/warnings through Collector. For field crews planning outdoor work, this would be a valuable layer and tool to have on a mobile app to support planning and safety. Unfortunately, basic map services like legends and labels are not supported through the app for these multi-symbol layers. After doing some digging, these layers can be pop-up enabled, but each layer has to be turned on individually.
It also needs a legend for editable layers too. eg. in the case where they only have update capability and cannot see the feature create menu pallet.
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