Apple Watch · HealthKit · iOS

Recovery,
Calibrated to You.

Your Apple Watch already tracks your health. Kreev turns that data into a personal Recovery Score — based on your body, not a population average — so you know exactly how you're doing each morning.

$0 Hardware · Apple Watch · Your Baseline, Not Theirs
Join the Beta Waitlist

Our first beta has concluded — the next opens later in 2026

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Coming to the App Store

Coming soon.

$0 Hardware Uses your Apple Watch
Personal Baseline Compared to you, not averages
Open Algorithm We show our math
Privacy First Your data stays yours
The Recovery Score

One Number.
Your Entire Day.

Every morning, Kreev analyses your overnight biometrics — heart rate variability, resting heart rate, sleep quality, activity load, respiratory rate — and distills them into a single Recovery Score from 0 to 100. Not a guess. Not a population average. A precise reading of how your body recovered, compared to your own history.

65–100
Above Baseline Recovery above your personal norm
50–64
At Baseline Typical recovery for your body
35–49
Below Baseline Recovery below your personal norm
0–34
Recovery Needed Significant recovery deficit
BASELINE 35% 50% 65%
0%

vs your personal baseline

0 —

Recovery Compass

62ms HRV
52bpm RHR
7.8h Sleep
8,420 Steps
Your Personal Baseline

Your Score Compares You to You.

Most wellness apps compare you to population averages — norms built from studies that may not reflect your age, fitness level, or physiology. Kreev is different. It builds a rolling baseline from your own recent history and measures how today deviates from your normal. An elite athlete with a resting heart rate of 42 bpm and a weekend jogger at 72 bpm both get scores that reflect their individual recovery — because the reference point is always you.

01
Wear

Your Apple Watch collects heart rate, HRV, sleep, steps, respiratory rate, and VO2 Max throughout the day and night.

02
Baseline

Kreev builds a rolling average of your recent 7–60 days. This is your personal normal — unique to your body.

03
Score

Each morning, today's metrics are compared to your baseline using Z-score statistics. The result is your Recovery Score.

Biometric Intelligence

Seven Signals. One Picture.

Every metric has a story. Kreev reads them all.

Training Load/Strain
A daily measure of cumulative physiological demand from exercise and activity. When strain is high relative to your baseline, Kreev flags it so you can balance load with recovery.
0%
LOW
Resting Heart Rate
0 bpm
Your heart's resting efficiency. Lower trends signal improving cardiovascular fitness.
Heart Rate Variability
0 ms
The variation between heartbeats. Higher HRV correlates with better autonomic recovery.
Sleep Duration
0 hrs
Total sleep versus your baseline. Consistency indicates more than one good night.
Steps / Activity
0
Daily movement load. Kreev tracks whether activity is adequate — or pushing too hard.
Respiratory Rate
0 br/min
Breathing rate during sleep. Subtle changes can signal shifts in recovery status.
VO2 Max
0 ml/kg/min
Peak oxygen uptake — your aerobic ceiling. Tracked over months to measure fitness trajectory.

See it in the app

Kreev app — Recovery Score dashboard
Kreev app — Biometric metrics view
Kreev app — AI wellness narrative
Kreev app — Training Load/Strain and trends
Kreev app — Metric drill-down detail
Recovery Insight AI · Gemini
64 Recovery Score
HRV 54ms ▼ −7%
Resting HR 56 bpm ▲ +2 bpm
Sleep 7.1h — Baseline
Deep Sleep 18% — Baseline
Activity Load 6,820 steps — Moderate

Your recovery score of 64 indicates you are tracking at your personal baseline today. HRV at 54 ms sits 7% below your 30-day average of 58 ms, pointing to mild residual autonomic load — likely from recent training sessions. Resting heart rate at 56 bpm is marginally elevated from your typical 54 bpm, consistent with moderate, unresolved physiological demand. Sleep duration of 7.1 hours and deep sleep at 18% of total time are in line with your recent norms. Yesterday's moderate activity load leaves no significant cumulative strain. You are recovered to your typical level — a standard training day is appropriate.

AI Intelligence

Your Score, Explained in Plain Language.

Every morning, Kreev generates a personalised narrative that explains exactly why your Recovery Score is what it is. Powered by Google Gemini, these narratives analyse your overnight metrics, compare them to your personal baseline, and describe the patterns in clear, analytical language. No medical jargon. No vague advice. Just your data, interpreted.

Anonymized data only — no names or identifiers are sent to AI

Google does not use your data to train or improve its models

You can request an explanation of any day's score

What a low-recovery day looks like
Recovery Insight AI · Gemini
41 Recovery Score
HRV 38ms ▼ −28%
Resting HR 68 bpm ▼ +16 bpm
Sleep 5.2h ▼ −1.9h
Deep Sleep 9% ▼ −10pp
Activity Load 14,200 steps + workout ▲ High

Your recovery score of 41 signals that your body is still processing yesterday's demands. HRV at 38ms is 28% below your 7-day baseline — a strong indicator of elevated sympathetic activity. Resting heart rate rose to 68 bpm, 16 beats above your recent average, consistent with unresolved cardiovascular stress. Sleep duration of 5.2 hours fell well short of your typical 7.1 hours; deep sleep accounted for just 9% of total time, limiting restorative physiological repair. High activity load from yesterday contributed significant cumulative strain. Consider a lighter training day and prioritise an earlier sleep onset tonight.

Kreev doesn't compare you to other users. A score of 41 means you are below your normal — not that you scored in the bottom half of all athletes. Context is everything.

Sentinel

Unlock Your Full Autonomic Intelligence.

Kreev is free to explore. Sentinel gives you the complete picture.

Recovery Score

Your daily 0–100 readiness number, computed from 6 biometric signals compared to your personal baseline.

AI Narrative

Full daily analysis powered by Google Gemini — explains your score in plain, analytical language every morning.

Training Load/Strain

Daily cumulative physiological demand from exercise and activity, tracked against your personal baseline with trend visualization.

VO2 Max & Aerobic Trend

Your VO2 Max number, always free. Sentinel adds ACSM percentile ranking and your 90-day aerobic trend against your own history.

Trends & History

Baseline stability charts, 90-day heatmap, and pattern insights across all your biometric signals.

Guardian Alerts

Push notifications when your recovery drops below your configured threshold — proactive pattern detection.

Full Drill-Downs

Z-scores, physiological position, analysis and compass tabs for every metric — every day, in full detail.

Recovery vs Strain

Side-by-side daily view of how your recovery and training load interact — exposing patterns in effort and adaptation over time.

Healthspan Index

A composite 0–100 score from five components: aerobic capacity, HRV, resting heart rate, sleep, and sleep regularity — you can add up the numbers the app shows and get your own score.

This Week's Training

Daily intensity recommendations based on your Recovery Score — showing optimal windows for hard effort, moderate work, and rest throughout the week.

Sleep Consistency

Tracks the regularity of your bedtime, wake time, and sleep duration across the week — because consistency matters as much as total hours.

Fitness vs Fatigue

A rolling view of fitness gain against accumulated fatigue — helping you identify when to push and when to back off for optimal long-term adaptation.

Free, forever: Recovery Score, Training Load/Strain, VO2 Max (the number), today's overnight metrics (current-week trends), and Trends tab charts (current month) — Sentinel extends both to up to 6 months. The History tab is Sentinel-only. No credit card, no time limit.

Transparency

We Explain How Your Score Works.
No Black Boxes.

Most wellness apps treat their scoring algorithms as trade secrets. We believe you have the right to understand how your data is being interpreted. Kreev publishes its scoring methodology, names every company that touches your data, and gives you the tools to control, export, or delete everything.

Algorithm Transparency

Your Recovery Score uses Z-score statistics against your personal rolling baseline. We explain the methodology in our Terms of Service — no black boxes.

No Demographic Profiling

Your score doesn't factor in age, sex, or ethnicity. Every user is compared to their own history — not a population average.

No Ads. No Tracking.

We don't use advertising cookies. We don't sell your data. We don't share it with data brokers. Ever.

Your Rights, Documented

CCPA opt-out. MHMDA consumer health data rights. PIPEDA compliance. Algorithm explanation on request. Delete Account for full removal, Reset This Device to clear your data locally.

Read our Privacy Policy, Terms of Service, and Consumer Health Data Policy.

Your Journey

Recovery Is Not Rest.
It's Strategy.

You train hard. You push limits. But the difference between progress and plateau isn't how hard you go — it's how well you recover. Kreev gives you the data to train smarter, sleep better, and understand the signals your body sends every day. Your baseline is your starting line. Your Recovery Score is the compass.

Join the Waitlist

Free forever. Sentinel included free for your first 30 days — no credit card required.

Pricing

Free forever. Sentinel for the full picture.

Your Recovery Score, Strain, and VO2 Max are free — no hardware, no expiry. Sentinel adds the AI interpretation layer for $5.99/mo or $39.99/yr (~44% off), with a 30-day free trial included on every new account.

Feature Free Sentinel
Recovery Score ✓✓
Training Load / Strain ✓✓
VO2 Max (number only)✓✓
Today's Metrics (HRV, RHR, Sleep, Respiratory Rate, Steps, Activity — Free: current-week trends. Sentinel: up to 6 months.)✓✓
Trends Charts (Free: current month. Sentinel: up to 6 months.)✓✓
AI Daily Narrative + Weekly Debrief + Month in Review—✓
Top Contributing Factors ("Why") —✓
Recovery vs Strain —✓
VO2 ACSM Ranking (category, percentile, next-tier target)—✓
Healthspan Index (5 components) —✓
Trends Long-Term Direction + prior months —✓
History Tab (Sentinel Pattern, Recurring Bottleneck, Your Patterns, monthly heatmaps, Autonomic Balance) —✓
Guardian Alerts —✓

Every new account gets a 30-day Sentinel trial automatically — no credit card required. At day 30, your account reverts to Free (no data lost) unless you subscribe. Cancel anytime; we remind you before renewals.

Join the Waitlist
Frequently Asked Questions

Questions? We've Got Answers.

Your Recovery Score (0–100) reflects your body's readiness based on your personal baseline. It is computed from sleep duration, heart rate variability, resting heart rate, activity load, and respiratory rate — all compared to your own recent history using Z-score statistics. Scores above 75 indicate high readiness; below 50 suggests your body may benefit from more recovery time.
An iPhone running iOS 16 or later and an Apple Watch Series 4 or newer (watchOS 9+). Series 4 and above support all 6 biometric signals. Older Apple Watch models support basic metrics but lack respiratory rate and VO2 Max.
Kreev compares your metrics to your own personal baseline — not population averages. We publish our scoring methodology, name every company that touches your data, and offer algorithm transparency that no other wellness platform provides. Plus, there's no hardware to buy and no 12-month commitment.
No. Kreev is a personal health informatics tool. It provides analytical observations about your biometric patterns — not medical advice, diagnoses, or treatment recommendations. Always consult a healthcare professional for medical concerns.
Training Load/Strain (0–100) quantifies the cumulative physiological demand your body is under from exercise, sleep debt, and autonomic stress. LOW (0–34) — your body is managing stress well. MODERATE (35–64) — normal training stimulus. HIGH (65–100) — significant load; prioritize recovery before your next hard session.
Every morning, Kreev sends your anonymized metric values (no names or identifiers) to Google Gemini, which generates a plain-language explanation of your Recovery Score. Google does not use this data to train its models.
No. Kreev does not sell your data. We share data only with the service providers needed to operate the app (Google Cloud for hosting, Google Gemini for AI narratives, RevenueCat for subscription management). No advertisers, no data brokers.
Yes. In the app, go to Settings → Delete Account and confirm. This permanently deletes all health metrics, scores, narratives, and account data from our servers. This action is irreversible. A separate "Reset This Device" option clears data locally on your phone without deleting your account.
Free, forever: Recovery Score, Training Load/Strain, VO2 Max (the number, always), today's overnight metrics (HRV, RHR, Sleep, Respiratory Rate, Steps, Activity) with current-week trend data, and Trends tab charts (current month). The History tab is Sentinel-only. No credit card, no time limit. Sentinel extends trend history to up to 6 months for both Today's Metrics and Trends, adds the AI daily narrative, Weekly Debrief and Month in Review, the "Why" contributing-factors analysis, Recovery vs Strain, VO2 ACSM ranking, Healthspan Index, the full History tab, and Guardian Alerts.
New users get 30 days of full Sentinel access — no credit card required. At the end of the trial, your account downgrades to the free tier. No data is deleted. You can subscribe at any time to restore Sentinel features.
Because 50 means "at your normal," not "half recovered" — the scale is anchored to your own baseline, roughly ±15 points per standard deviation of your own variation. An ordinary morning scores around 50 by construction; an 80 is genuinely exceptional. Apps whose scores usually sit in the 80s and 90s have let the top of the scale stop meaning anything. Ours doesn't flatter — that's the point.
No. The 30-day Sentinel trial requires no credit card and does not auto-charge. If you choose to subscribe afterward, we remind you before renewals. Cancel anytime in iPhone Settings → Apple ID → Subscriptions.
Yes. In the app, go to Settings → Export to download all your health metrics, scores, and narratives as a single JSON document.
We take privacy seriously. Read our Privacy Policy, Terms of Service, and Consumer Health Data Policy. We comply with CCPA/CPRA, MHMDA, and PIPEDA. You can opt out of automated scoring and request an explanation of any day's Recovery Score.
Contact us at support@kreev.app. You can also access the Help section within the app (Settings → Help).
Beta Concluded · Next Cohort Later in 2026

Our First Beta
Has Concluded.

Thank you to everyone who tested Kreev with us. An upgraded beta opens later in 2026 for residents of the United States and Canada (excluding Quebec) — join the waitlist to be first in line.

Join the Waitlist →

Apple Watch Series 4+ · iPhone iOS 16+ · 18+

Get Started

Start Understanding Your Recovery.

Free forever. No hardware required. 30 days of Sentinel included, no credit card.

Requires iPhone with iOS 16+ and Apple Watch Series 4+