I'm glad to see this app here, because after trying many, many to-do/habit tracking apps, this is the only one that has stuck. I've been using it for about two months now, and I'm/we're still going strong. I've have always wanted a non-intimidating, very simple list of things I could simply mark as DONE every day, and this is it.
In the market there are several similar apps. I believe the latest one learn form the others.
