I have a feature service published through ArcGIS Server that I'm testing in Collector Classic and the new Collector on Android. It includes a point layer with attachments and user-defined editor tracking fields as well as a related table with identical editor tracking fields. I've made a very simple web map with just these items as well as the National Geographic basemap to use in Collector. I've tested it out on two different Android tablets (Samsung Galaxy Tab A running Android 8.1.0 and Samsung Galaxy Tab S2 running Android 7.0) and had a co-worker test it on a 3rd Android tablet and an iOS device.
In Collector Classic, the service performs as expected; no issues.
In the new Collector, the basemap loads but none of the points do. Going to the "Layers" tab I see an orange triangle with an exclamation point and the text "The field already exists" under the layer name. Additionally, the iOS device included the error code 3018. Looking through questions others have posted, I found some similar issues which all seemed to be related to the editor tracking fields, especially the ones tracking users:
Collector for ArcGIS layer error Code:3018
Map Downloads with Collector Classic but not the New Collector
Layer failed to load- red triangle
I confirmed that the editor tracking fields had something to do with it, as disabling the "Keep track of who created and last updated features." setting on some identical test hosted feature services I published (I don't have access to edit the ArcGIS Server service) allowed the layer to load. The most likely-sounding solution from the above posts was to adjust nullability and defaults on my custom editor tracking fields.
However, testing a number of combinations of editor tracking field settings (allow nulls, don't allow nulls, no defaults, different defaults for each) did not solve the issue. I also tried removing the related table that had identical editor tracking fields with no success.
Another complicating factor is that when I tried enabling developer options in Collector (triple-tapping my user name) to access log files, a brief pop-up says "Developer options enabled" but when I clicked on "Developer Options" in the menu, all I see is "Placeholder". I don't think my organization/device is limiting this as I can enable Android developer options on the tablet; should this function be operational on the Android app or is it not there yet (ver 20.2.0)?
Hoping for a solution that lets me use this data in the new Collector, any guidance would be appreciated!