Happy to have found this discussion. I think similar to Teresa, I was confused about how Survey123 documentation suggests publicly available forms are supported, and yet, you can't login to the survey123 app without an organizational account. The link option described above does work, which is nice, but not straightforward.
The primary reason we would prefer the app over a browser is that our users are collecting information in offline environments.
Why not allow public AGOL accounts to login to the survey 123 app? Would be nice to be able to know who submitted the data without requiring a text field to be filled out each time a record is created. Would also be nice if a user could use the "download surveys" approach rather than have to use a link sent to them in an email.
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