The quiet patterns behind how you feel.

Tensi looks for real correlations between your life — meetings, recurring places, weather — and your body's own signals, like HRV, sleep and resting heart rate. Instead of just showing you charts, it tells you which parts of your day actually line up with how you felt.

For each pair — say, meeting load and HRV — Tensi compares the days a condition was present against the days it wasn't, and checks whether the difference is both large enough to matter and consistent enough to trust. It needs roughly 10 or more matching days before it will surface anything at all, and only shows the handful of strongest, most reliable findings — never every coincidence that happens to clear a low bar.

They summarize how reliable a finding is, based on how large the difference is and how consistent it's been across your own data — not a single unusual day. STRONG means a large, consistent effect. MODERATE means a real but smaller one. WEAK means a pattern worth watching, not yet conclusive.

Both measure heart rate variability from the same heartbeat data, just calculated differently. RMSSD is more sensitive to short-term, moment-to-moment changes; SDNN reflects variability over a longer window. Tensi shows both so you can look at the same story from two angles, alongside resting heart rate, sleep, activity and your other supported health data.

That's the lag between cause and effect. If a finding says a busy day correlates with lower HRV "the next day," Tensi is comparing what happened on day X against your HRV on day X+1, not the same day — some effects on the body show up with a delay, and Tensi checks for that rather than assuming everything is same-day.

No. Tensi surfaces patterns for your own awareness — it isn't a medical device, doesn't diagnose conditions, and doesn't provide treatment or medical advice. For anything health-related, talk to a qualified professional.

No. Every correlation is computed on your iPhone. Tensi has no backend server, no account system, and no analytics or advertising SDKs, so we never receive your data. The only thing that leaves your device is location coordinates sent to Apple's own weather and place-name services.

Health data (like HRV, sleep and heart rate) to compute correlations; Calendar, read as event times, durations, recurrence, attendee counts and location presence, never titles, notes or attendee names; and Location, to notice recurring places and fetch local weather. All optional, all analysed on your iPhone.

Yes. Tensi ships with a native watchOS companion app plus its own widgets and complications, so today's HRV trend is always on your wrist.

Free gives you today's vitals, the body metrics overview, and the full Apple Watch app. Tensi Pro unlocks the full Patterns correlation engine, the Recovery calendar and history, and Weekly Reports.

Tensi Pro is $1.99/month or $11.90/year, billed through your Apple ID as an auto-renewing subscription. You can cancel anytime from Settings → Apple ID → Subscriptions on your device — no need to contact us.

No. There are no ads anywhere in Tensi, and there's no data to sell in the first place — nothing is collected off your device.

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Reach out any time at burakoztirpan@gmail.com — or see the contact page.