Nothing on circadian rhytms
It doesn't show you the up and down cycles that change throughout the day to guide you. Wasted a dollar. Forget about a subscription.
Response from developer
Knowing is different from doing. The app and particularly the watch complications are designed to keep reminding users of good habits. Simple habits can go a long way for long term health.
Cool Idea that Needs to be Fleshed Out
Response from developer
More flesh is coming out in version 2, including bedtime notifications with activity detection. Glad to see more users benefiting.
Disappointing
Response from developer
Lighting is the primary signal for body clocks. There is more commonality than differences among people. Better to schedule based on sunlight and manage other light. Current useful features of the app include Apple Watch complications that serve as gentle reminders, study of year-round sunlight with time-travel, and guided (constrained) scheduling with gestures.