The Cards app shows the description; "Create interactive personal planning cards. " but I can't figure out how to do that. The picture in the app gallery depicts something that looks like a checklist/todo list but I don't see any features (prioritization, target date designation, completion check-off) that I would expect to see in such an app. I realize that cards constitute their own stream, as it were... is that pretty much the extent of it? Are Cards basically a separate stream of posts that can be added and deleted as, more or less, a list apart?