01
Allow Apple Health access
Sleep, resting heart rate, HRV, steps, and workouts. We read only what the charge calculation needs.
iPhone · Apple Watch
A daily energy score for iPhone and Apple Watch
Body Charge turns Apple Health data into a single number, 0–100: how much energy you have now, how much sleep gave you, and where it goes during the day.
Download on the App Store
Free core · optional Pro · no account
0–100charge scale
on-deviceall computation
4complication families
quick glance
Three steps
How it works
02
Computed on your device
The model estimates how much sleep charged you and how much the day spent. Health data is not sent to our servers.
03
Look at one number
Instead of a dozen charts, you get a 0–100 level, one sentence of guidance, and an evening forecast.
Features
What’s inside
Three screens that cover your morning, your night, and the weekly picture. Nothing more.
Charge
A level that moves with your day
Your charge updates through the day. You can see stress, training, or short sleep draining it, and how much will be left by evening.
- Forecast to the end of the day
- Confidence marker when data is thin
- A breakdown of where charge went
Energy today
Sleep
Sleep as the main source of charge
Duration, deep sleep, and REM with an explanation of what actually produced this morning’s number, not just a pile of percentages.
- Night structure by stage
- Accumulated sleep debt
- Bedtime consistency
Night contribution
Trends
Weeks, months, training load
Morning charge over time shows what works: earlier nights, easier sessions, and less coffee after lunch.
- 7- and 30-day trends
- Load versus your usual fitness
- Weekly summary in one line
Morning charge
Privacy
Health data never leaves your iPhone
Apple Health data and calculations stay on your devices. Release builds use Firebase for usage analytics and crash diagnostics without health values. Meta ad measurement is disabled.
Apple Health stays on-device
Health dataon-device only
Health backendnone
Diagnosticsanonymous Firebase
AdvertisingMeta disabled
Apple Watch
Your charge on your wrist
Complications for all four families plus a full-screen level. A glance instead of reaching for your phone.
Circularring with the number
Cornerlarge level
Inline“Charge 63”
Rectangularlevel and forecast
Method
What the charge is built on
A transparent model: you can see each source’s contribution instead of a magic score.
~50%
Sleep
Duration, structure, and consistency are the biggest contribution to the morning number.
~30%
Heart rate & HRV
Overnight resting heart rate and variability show how well your body recovered.
~20%
Load
Workouts and activity spend charge, weighted against your usual fitness.
Body Charge is a wellness app, not a medical device. It does not diagnose or treat anything, and it does not replace medical advice.
Daily rhythm
Why it’s easy to keep using
fast
One number instead of ten charts
Morning decisions stay quick. You glance at the level, see what changed, and move on with your day.
calm
No account and no health-data backend
The main signal stays on your device, so you get useful daily feedback without adding a health server in the middle.
glanceable
Apple Watch shows the signal without opening the app
Complications and the full-screen level put the only number that matters right on your wrist.
All guides
Apple Watch guides: energy, sleep and recovery
Practical explanations of Apple Health signals, daily energy and recovery. No medical promises or pressure to chase a number.
How to read your daily energy score on Apple Watch
Learn how to read a daily energy score from Apple Watch signals, what it can and cannot tell you, and how Body Charge keeps calculations private on-device.
How sleep and recovery shape your daily energy level
See how sleep duration, sleep stages, recovery signals, and daily activity shape a personal energy score on iPhone and Apple Watch.
What to look for in an Apple Watch energy tracker
A practical guide to Apple Watch energy trackers: which signals matter, how to read a daily energy score, and why context is more useful than a single number.
Does sleep restore energy? A practical way to read the signals
Learn how sleep duration, regularity, recovery signals, and daytime activity can shape daily energy context on iPhone and Apple Watch.
Common questions
A daily energy score for iPhone and Apple Watch
Body Charge is a private wellness app that makes Apple Health signals easier to read: one 0–100 level, sleep, recovery, and activity context without an overloaded dashboard.
What is Body Charge?
Body Charge is a daily energy score app for iPhone and Apple Watch. It turns Apple Health signals into a 0–100 scale so you can read your day at a glance.
Does Body Charge work with Apple Watch?
Yes. Body Charge supports Apple Watch and shows your energy level through complications and a full-screen view.
Where is Apple Health data stored?
Apple Health data and Body Charge calculations stay on your devices. Body Charge does not operate a backend that receives health data.
Is Body Charge a medical device?
No. Body Charge is a wellness app, not a medical device. It does not diagnose or treat anything and does not replace medical advice.
See your charge tomorrow morning
Install it, allow Health access, and your first number arrives after the next night.
Download on the App Store
Free · iOS 17+ · Apple Watch optional
iPhone · iOS 17 or later · Apple Watch (optional) · watchOS 10+