Philosophically speaking, this is the epitome of what Steve Jobs was thinking when he thought of the ideal app: a simple tool that, given the resources at your disposal, can turn average individual parts into a delightful greater whole. This app has done that for me.
A bug, though:
1) could apply to other ingredients, but for the sake of example: switch ginger on, then switch lemon on, then switch lemon off, then switch lemon on. The tally appears over the tab bar item and indicates a 0.
Appstache about Old Sport