trying to publish a layer from a file geodatabase to enable editing through collector or web app builder, but want to keep data local, not the AGO cloud. Is this possible?
Help is giving me mixed reviews:
1) unregister the data source from the server so that data can be copied to the server
2) register the data with the server to enable feature access
So can I please get a yes or no confirmation whether or not you can edit file geodatabase through a feature service?
No, that's not possible, but you can register the ArcGIS Data Store as your managed data store and when you publish file geodatabase data and select feature access, it'll copy the data into the ArcGIS Data Store so it can be an editable feature service, (note that the linked documentation refers to enterprise geodatabases but the content is relevant to ArcGIS Data Store). The data in the service will then point to the copied data instead of the original source data. You can always edit it in ArcMap by creating a local copy for editing.
If you're publishing to Portal and the data is copied into the ArcGIS Data Store, you have the option of creating a tile layer or hosted feature layer. If you're publishing a hosted feature layer, they can be edited in clients such as the web map viewer, any web application that supports editing, and desktop clients like Pro and ArcMap.