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Currently Incomplete and Saved form management can be disabled (as long as you are running CommCareODK 2.1 or above) by turning on CommCare Sense mode in the UI Settings for your app in CommCare HQ's app builder (select "true" from the drop-down menu next to CommCare Sense)
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How can I remove saved forms?
A saved form will automatically be deleted from your phone after 1 week. If If necessary the records can manually be removed from the device's local storage in the same manner as Incomplete forms.