Checklist App
I kept the app as simple as possible, with color-customizable lists ("Self-growth" example) and task completion, trying to figure out if it would be usable if I was shopping at the supermarket ("Shopping list" example).
I assumed users usually concentrate on one thing at a time, so in this respect I thought the "Done" items should be in the background rather than visible. Once a task is completed, it checks itself up then disappears into the Done list, and the task number counts down.
Done tasks are accessible by opening and closing the bottom panel and can be deleted if you don't want to see them anymore.
Lists and tasks editing (adding, renaming, deleting, color-changing, displaying extra notes with long content...) is mainly what the app is up to.