Yes, data remains on Narrative Science's servers until an app or org is deleted. Deletion/removal of your organization or any app within your organization results in a complete deletion of your data.

 

To delete an app, you must have admin access. Navigate to the Data page from your left sidebar.

 



 

On the Data page, hover over the top right corner of any app to pull up the options menu. Click "Delete Connection" to delete this app.