An argument could be made to say the most important app that Apple ever created is their Health App.
Apple’s Health app is an absolute treasure trove of good, useful, insightful data. Combining it with an Apple Watch (and other sensors, such as my Oura Ring) make its capability crazy good.
Its only limitation from a quantified-self enthusiast’s perspective is its lack of (good) mechanisms to “correct” data. While you absolutely can manually add data, it’s less easy to manually correct inaccurate data… and it’s on you to find these inaccuracies. Automated Tracking, Manually Confirmed is my gold standard, and the app only really excels at one of the two.
It natively supports tracking:
- Sleep Duration and some portions of your Sleep Hygiene
- Duration & type of Exercise
- Running/biking/swimming speed, cadence, distance, etc
- Steps, sedentary time, and the standard pedometer stuff
- Including METs, which I didn’t know about
- Body measurements (Weight, height, etc)
- Macros & Calories
- Medications
- Mental wellbeing
- Respiratory info
- Rate
- O2 level
- VO2 Max & Cardiovascular fitness
Source
- Self