WatchME

For people with ME/CFS. This app helps you to pace and stay within your energy envelope. Use your phone and watch to monitor your daily heart rate, steps and distance.
Integrated with HealthKit.
This app uses the Health app to monitor resting, average and maximum heart rates, heart rate variability, step count, walking distance and active energy.
Set your individual thresholds for nominal, caution, warning and critical levels. Keep an eye on your status on phone and watch. Add complications to your watch face to alert you when you cross thresholds.
Please note: currently at least one complication is required on the active watch face for background alerts. Alerts on the watch are not instantaneous - background checking occurs every few minutes during the day.