Looking for an easy way for users to be able to select features interactively by rectangle (e.g. the Select tool in Desktop) and then have some way to modify the styling (say, change the color) of the selected features. The changes would need to be saved too, so can't just do browser-side styling only.
Here's an example of the scenario I'm thinking of:
Adam and Bob are discussing some parcels. To clarify the discussion, Adam makes a map on AGOL containing a layer of parcel features. He makes the parcels he's referring to show up as blue and sends Bob a link. Bob sees the blue parcels but has a few changes to make, so selects a few additional parcels and changes their color to red. Adam is able to see Bob's changes.
What's the easiest way to do this without having to use Desktop? Assume a parcels (or something like it) feature service (or KML, geoJSON, etc) has already been created.