How Kelesto works
Kelesto explains. You set the pace.
Kelesto takes the Apple Health data you allow, compares today with your own baseline and calculates your Recovery, Stress and Load, with plain notes on what moved them.
- 01 Apple Watch records
- 02 Apple Health stores
- 03 Kelesto explains, on iPhone
Getting started
Four steps, then let it learn.
Download Kelesto on iPhone
Kelesto is an iPhone app for iOS 17 or later. There is nothing to install on the Watch.
Pair and wear your Apple Watch
Wear it through the day, and to bed if you want sleep and overnight recovery context.
Allow Apple Health access
iOS asks which data Kelesto may read. Kelesto only reads it and never writes to Apple Health, and you can change access at any time.
Open Kelesto
You see what your data already supports. The rest fills in as Kelesto learns your baseline.
What shows up, and when.
Not every score appears on day one. Kelesto needs recent data and some history to compare against, so these depend on wearing your Watch each day, including overnight for sleep.
- First sync
Kelesto reads the data you allowed and starts learning your baseline.
- About 3 days
Stress readings usually appear. They get more accurate over the next two to three weeks.
- About 7 days
Your first full Trends readout across recovery, sleep, stress, load and more.
- About 30 days
Your first monthly report. Vitality Age reviews need enough qualifying days too.
Signals become context
What Kelesto works out from what your Watch measures.
Apple Health holds measured records. Kelesto calculates its readings from them, against your own baseline. The two are kept apart here, as they are in the app.
Overnight
Measured by Apple Watch, stored in Apple Health:
- Sleep
- Overnight heart rate
- HRV
- Resting heart rate
Optional: Wrist temperature and blood oxygen, where your Watch records them
Calculated by Kelesto:
- Recovery
- Sleep context
How today’s overnight signals compare with your usual range, with sleep as the context.
Through the day
Measured by Apple Watch, stored in Apple Health:
- Heart rate
- HRV
- Resting heart rate
- Movement
Calculated by Kelesto:
- Stress estimate
- HRV against baseline
Whether your body appears calm, activated or still recovering. A wellness signal, not a diagnosis.
Training
Measured by Apple Watch, stored in Apple Health:
- Workouts
- Steps
- Active energy
- Cardio fitness (VO₂ max)
Calculated by Kelesto:
- Training Load
- Progress over time
How much demand your recent training carries, read beside how recovered you are.
In the app, a calculated reading comes with plain notes on what moved it and over what period.
See every metric, definedA day with Kelesto
One app, from the first glance to the long view.
Morning
Check where today sits.
Home gives you a morning snapshot of yesterday’s data. Recovery shows today against your recent average, with Kelesto Insights explaining what moved it.
Before training
Read the plan beside your load.
Your weekly plan sits next to Stress, Load and recovery. When load is high and recovery is low, Kelesto may suggest keeping the session controlled. The call is still yours.
Across the week
See what you actually did.
Train marks done, missed and rest days on a consistency calendar, beside your cardio fitness. It also keeps your workout history and personal records.
Over the months
Follow the longer pattern.
Trends by week, month and quarter, step and active-calorie goals, and a monthly report you can save as a PDF or share.
Kelesto offers wellness guidance to support your own decisions. It is not medical advice and does not prescribe training.
What’s inside
Start with today. Go as deep as you like.
Every morning
The daily decision.
- Morning snapshot
- Yesterday’s data, summarised on Home.
- Recovery
- Today against your own range.
- Stress
- An estimate of current physiological load.
- Load
- The demand your recent training carries.
- Sleep
- Duration and consistency, as overnight context.
Every week
Training with context.
- Weekly Train plan
- Your sessions, read beside recovery and load.
- Workout history
- Imported Apple Watch workouts and a consistency calendar.
- Personal records
- Your best efforts, logged by exercise.
- Step and active-calorie goals
- Daily targets you set, tracked on Home.
Over time
Progress you can see.
- Trends
- Week, month and quarter views across your signals.
- Vitality Age
- A slow-moving wellness estimate, reviewed each cycle.
- Monthly report
- A full-cycle summary to save as a PDF or share.
- Levelling
- Streaks, badges and a yearly ladder for consistency.
- Friends and Clubs
- Share the signals you choose with people you approve.
Compatibility
Works with Apple Watch Series 5 and later, and every Ultra.
Kelesto runs on an iPhone with iOS 17 or later, and reads the Apple Health data your Watch records and you allow. It doesn’t need the newest watchOS.
Apple Watch Series
- Series 5
- Series 6
- Series 7
- Series 8
- Series 9
- Series 10
- Series 11
- Series 12
Series 5 through Series 12
Apple Watch Ultra
- Ultra
- Ultra 2
- Ultra 3
- Ultra 4
All Ultra models
Apple Watch SE
Not yet confirmed
Kelesto reads whatever an SE saves to Apple Health, but we haven’t yet confirmed which insights each SE model supports, so it isn’t listed as compatible.
What you see depends on your Watch. The data and insights available vary with model, sensors, region, permissions, how often you wear it and how much history has built up. For example, wrist temperature needs Series 8 or later or an Ultra, and blood oxygen isn’t recorded by Series 5 or available in every region. Kelesto treats signals like these as optional.
- iPhone with iOS 17 or later
- No Watch app to install
- Read-only Apple Health access