Ah, with this comment I found the Health kit (https://developer.apple.com/health-fitness/) which would suggest that if I had my own app, then it could do everything on its own it seems. Good stuff! Source: 12 months ago

Your smartwatch knows your exact body functions, knows when you exercise, fall, sit too long (for whatever reason 💩) or are experiencing stress. All of this data is available through the respective apps or a central app on your platform, e.g. HealthKit on iOS. - Source: dev.to / almost 2 years ago

Apple has HealthKit for apps. Maybe start there? Https://developer.apple.com/health-fitness/. Source: over 2 years ago

For example, Apple's HealthKit is an app for Apple devices that provides users with a centralized view of health and fitness data tracked over time on their iPhones or iPods. It allows the data to be shared among different apps so you can see how various factors influence your overall health. - Source: dev.to / over 2 years ago

I found another Https://habitlist.com/ I can see it's kind of similar. Source: almost 3 years ago

I've had good results for the past ~6 months using Habit List [0]. What's worked for me is to slowly add 1-2 new items, being thoughtful about prioritizing them. Then when I'm consistent with those, adding more. [0] https://habitlist.com/ (ios only, just a happy user). - Source: Hacker News / almost 3 years ago