Maybe this will help you do what you need to:
Looks like Chad Yoder's link is a solution, but requires the end user to be a coder, a more elegant solution would be better.
This would be useful where you use Survey123 to create a feature layer and a domain is initially created based on a choice list. If you later add new entries to the choice list and republish, the domain is not updated. If you are then using this data in a dashboard you can not see the new value in filter options. An efficient way to quickly update domains would be ideal in this situation.
Starting with the June 2018 update you can now define attribute lists and ranges for your data.
Define attribute lists and ranges—ArcGIS Online Help | ArcGIS
Okay now please allow 0 (zero) to be added as one of the coded domain values when using the AGOL interface. I can enter 0 as a domain value through the coding route (i.e., Chad Yoder's solution above), but I can't do it directly using the new "easy" method; it will not save if one of the values is 0.
I have existing domains that already have a zero, and they work fine, but if I want to add another coded value I can't do it in the AGOL interface because of the pre-existing zero.
Do I need to write this up as a separate idea?
Retrieving data ...