Gamified App Precedents

http://yukaichou.com/lifestyle-gamification/the-top-ten-gamified-productivity-apps/

http://habitica.wikia.com/wiki/Drops

Many of these apps punish players for not completing tasks, with a focus on productivity and generating healthy habits rather than anxiety and managing the complications of life, which is what I aim to do.
I have observed that many of these are very complicated and UI heavy, which I want to keep away from in favor of something more minimalist and calming.