We have an ArcGIS server with REST API, containing some feature layers we want to edit also on machines without ArcGIS Desktop, ideally through ArcGIS Collector. We don't have the Portal, but we have ArcGIS Online organization account. However, this says that only hosted layers can be set edittable, and maps without edittable layers seems to be invisible for ArcGIS Explorer. We can't afford keeping all the layers to be editted as hosted ones.
This answer mentioned working directly with the feature server's services, so it should be possible, even though I didn't find how to do it in a day of searching. So how to make the Collector work with the layers without hosting them to AGOL?