@Jeffrey Goller, Thanks for posting in Q&A. For the app configuration policies for managed iOS/iPadOS devices, it is listed in the following link:
https://learn.microsoft.com/en-us/mem/intune/apps/app-configuration-policies-use-ios
And for your request, if it is an Intune enrolled device, you can set the following app configuration policy to let the enrolled user to login the managed app.
Hope the above information can help.
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