It seems to me that Beeminder has put a ton of thought and effort into the experience that triggers a penalty with the user always in control. I see this as much more flexible than the non zero day app. It also appears that beeminder has a freemium offering and this payment&#x2F;penalty is a feature more than the whole point. In other words, I see the charges on beeminder to be similar to paying for extra lives on candy crush as a one time in app purchase... as opposed to model that the pricing gimmick is basically the core offering.<p>Edit: cool app btw, gonna give it a try :)