Regardless of my free version this app's intention is to help it's users increase positive habits and reduce negative habits. For someone like me who needs feedback, the percentage of success gives me an incentive and motivates me to keep the chain going. After using this app for almost two months I have been able to analyze and critique a few of the apps features. It would be interesting to know scientific statistics of the success of the app and if it is successful in what it is set out to do. In regards to the level of engagement I would say that the percentage strategy keeps me coming back to this app. For functionality, the free version runs smoothly, is clear, and easy to use. For aesthetics, it is simple and convenient however I do think that for some users it might be difficult to see due to size of buttons and font size. The information is a bit outdated and needs to be cited and should come from more credible sources. I do enjoy seeing that there is a discussion board for communication between users. From my subjective analysis this app's rating is a 4.1.