Tawen: HRV & Readiness Score

Every readiness app hands you a number. Tawen tells you what it means.

Tawen reads the sleep, heart rate variability (HRV) and activity your phone already records through Health Connect, turns it into a daily recovery score from 0 to 100, and explains it in plain English — written by AI that runs entirely on your phone. A number with a why. And nothing leaving your device. A private recovery tracker and readiness tracker for any wearable you already own — your wellness score, computed on-device.

— EXPLAINED BY ON-DEVICE AI —
When your score is ready, Gemini Nano (Google's on-device AI) writes a short, plain-English note on how your day unfolded — whether your readiness climbed, dipped and recovered, held steady, or faded, and what's driving it. It runs locally on supported phones; your health data is never sent anywhere to generate it. On other phones a dependable rule-based explanation takes its place, and your score is identical. We only call it AI when AI actually wrote it.

— FIVE SIGNALS, ONE HONEST NUMBER —
Your readiness score is a weighted blend of five signals, calibrated to your own baseline:
- Sleep (35%) — duration and sleep stages
- Cardiovascular (25%) — heart rate variability (HRV) and resting heart rate vs your baseline
- Activity (25%) — movement balance, so you neither under-recover nor over-train
- Body oxygen / SpO₂ (10%) — overnight blood oxygen tracker (SpO2 saturation)
- Thermal (5%) — skin temperature vs your baseline

— HONEST WITH YOUR DATA —
Tawen doesn't just average whatever it finds. Missing a signal? It scores what it has, re-weights the rest openly, and tells you the score is partial — it never invents a number to fill a gap. Conflicting step counts? It trusts your wearable, not the sum of every counter on your phone. You can always see exactly what went into your score.

— NO SUBSCRIPTION. NO WEARABLE LOCK-IN. —
Most recovery scores live behind a monthly membership or a band you have to keep wearing and paying for. Tawen is a private, one-time-purchase alternative to subscription wearables like Whoop and Oura — and to brand-locked scores like Garmin Body Battery — that works with the phone and wearable you already own. No $30-a-month membership. No new hardware.

— PRIVATE BY ARCHITECTURE —
- All scoring and AI run on your device
- Only derived scores are stored — never your raw Health Connect records
- Read-only: Tawen never writes back to Health Connect
- Analytics and crash reporting are off by default, opt-in only, and never carry health values
- No ads, no data brokering, no selling, no account
- Delete everything with one tap in Settings

— UPDATES THROUGH YOUR DAY —
Tawen snapshots your latest data every hour, so your score keeps up — in the morning, at check-ins through the day, when you open the app, and on pull-to-refresh.

— WORKS WITH WHAT YOU OWN —
Any Android 9+ phone, and any wearable that writes to Health Connect — Garmin, Galaxy Watch, Pixel Watch, Fitbit, Oura, Whoop and more. Garmin users: turn on Health Connect in Garmin Connect to sync automatically (HRV needs the optional Health Sync bridge app).

— ONE PURCHASE, FOREVER —
Tawen is free to download. A single $4.99 purchase unlocks Pro — no subscription, ever:
- 90 days of history (Free keeps 7)
- The full daily insight
- Weekly reports — what drove your week, in plain English

Built by one independent developer. The free app is genuinely complete; Pro is simply how an indie project keeps the updates coming.

Not a medical device. Tawen is a general wellness tool and does not diagnose, treat, cure, or prevent any condition. Always consult a qualified healthcare professional for medical decisions.

Privacy: https://tawen.app/privacy