This article shares some possible use cases your app could support, as well as an example flow that could support each use case. You're certainly not limited to these use cases, but they can be a helpful jumping off point as you plan your app's implementation.
A visitor signs up on your app to receive non-transactional content. If the visitor is from a country where the opt in level is double confirmation, follow this flow to create the marketing consent and update the visitor's marketing consent state.
To confirm the marketing consent:
state
property of the response is PENDING
until the visitor confirms the sign up.PENDING
to CONFIRMED
.