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Create rules on CommCareHQ to automatically close cases that are no longer relevant. Read more here.
Case Management
You can use Case Management to save anything you want to be able to edit to the case.
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An app can contain "edit" forms that load in the previous values of case properties, and allow users to update them. This then updates the value of the case property, so that the case details/export contain the most recent values. Details on the workflow can be found at How can your user edit data? and a tutorial on how to create the Edit From can be found at Edit Form Tutorial.
Administrative Application
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