Here are some options that might help: Option 1:*Note: I don't know how reliable this platform is; I found it with a quick search.Use this public web app https://jsonserve.com/ that allows to create a JSON and serve it with API. For example, you can open it and put this JSON:[ "A", "B", "C" ]...

Thanks a lot for tagging me here; this is definitely in our backlog. Let me see what we can do to accelerate this and have new experience applied to Expenses as well!

Thanks for the feedback Sarah!We are looking to find ways to simplify the selection of the JSON path.  As this is an API integration field, we need to have some way to understand which value from the payload we should display as a dropdown option. The best way to provide a configurable and powerful ...

Thanks for the feedback, William! May I ask you to provide more details on this feedback? What do you mean by a new object type? I'm happy to jump to a call to discuss this. 

Hi Doug, William has a great response above detailing how the cascading works using this new field type. Thanks,Gagik

Hi Mylah, I'm happy to let you know that we have added the External Lookup field type to custom forms that might cover your needs. It is already in preview and will be release with the upcoming release. Here you can find more details on that. ThanksGagik