Frequently Asked Questions

Sextant Vitality is an iPhone app that takes the HealthKit data you already collect — VO₂max, HRV, sleep, walking speed, resting heart rate, workouts — and distills it into one composite Vitality Score (0–100), tuned for midlife men. It also tracks blood lab results and lifestyle interventions so you can see how they relate to your bearing over time.

Men aged roughly 35–60 who already use an Apple Watch and Apple Health, who get blood work done once or twice a year, who want to optimise without becoming a biohacker. If you've heard of Peter Attia, Andrew Huberman or Bryan Johnson but don't want to be them, you're the audience.

The score is a weighted average of six sub-scores: Cardiorespiratory (VO₂max, weighted 30%), Sleep (20%), Recovery / HRV (15%), Activity (15%), Cardiovascular / RHR (10%), and Mobility / walking speed (10%). Each sub-score is normalised against age- and sex-adjusted reference ranges (Cooper Institute / ACSM percentile tables). When data for a sub-score is missing, the remaining weights re-normalise — so partial HealthKit permission still produces a usable score.

No. Sextant Vitality is a self-understanding tool, not a medical device. It does not diagnose, treat or prevent any condition. The Vitality Score is a wellness indicator. Always consult a qualified physician for medical advice — especially before any change to medication, supplements, or hormonal therapy.

VO₂max, Heart Rate Variability (SDNN), Resting Heart Rate, Walking Speed, Sleep Analysis, Apple Exercise Time, Step Count, Workouts, and optionally Body Mass / Body Fat. All read-only. You can grant or revoke any of these individually.

Strongly recommended. VO₂max, HRV and overnight resting heart rate all come from Apple Watch. Without a Watch the score still works but several sub-scores will be unavailable.

The score adapts. Each sub-score is computed independently; missing ones drop out and the remaining weights are renormalised. The Today screen shows a "data completeness" cue so you know how much of the picture is filled in.

No. HealthKit data, lab values and intervention logs all live on your device. The only outbound traffic in v1.0 is Apple's StoreKit (for purchases) and the contact form (only when you tap Send). See the Privacy Policy for the full breakdown.

25 panels covering hormones (Total T, Free T, SHBG, Estradiol), prostate (PSA), lipids (ApoB, Lp(a), LDL-C, HDL-C, triglycerides), metabolic (HbA1c, fasting glucose, fasting insulin), inflammation (hs-CRP, homocysteine), thyroid (TSH, Free T4, Free T3), nutrients (Vitamin D, B12, Ferritin, Magnesium), and others (Hematocrit, Creatinine, ALT). Unit conversion (e.g. ng/dL ↔ nmol/L) is automatic.

Not in v1.0. Manual entry with unit conversion is the v1.0 experience. Apple Vision-based OCR for Quest / LabCorp / Hone Health PDFs is planned for v1.1.

Sauna, cold plunge, fasting, alcohol-free runs, new supplements, new training blocks — these are the things midlife men actually try. Logging them puts a marker on your Trends chart so you can see whether your Vitality Score moved with the intervention or independently of it. v1.0 shows the markers; v1.1 will run automatic before/after effect-size analysis.

That's a conversation for your physician, but the app will gently flag a "follow-up" reminder when six months have passed since your last entry — the rough cadence many midlife men aim for.

Today's Vitality Score, the HealthKit metrics row, intervention logging, three lab panels, the past 30 days of trends, and JSON / CSV data export. Enough to use the app daily, forever, without paying.

All six sub-scores, full history (90 days, 1 year, all-time), the age-cohort comparison band on Trends, intervention markers overlaid on the chart, unlimited lab panels, and the monthly PDF report. $8.99 / month or $79.99 / year.

Because some midlife men prefer to settle a tool once and not think about it again. The Lifetime tier ($179.99) is a one-time purchase, available during the launch year only, that unlocks Premium forever. After the launch year it goes off sale; existing Lifetime holders keep their access.

Yes — 7 days on the yearly Premium plan, for new subscribers. The monthly plan has no trial: at $8.99 the commitment is small enough that the trial isn't necessary, and Apple only allows one trial per subscription group anyway. Eligibility is determined by Apple based on your subscription history.

Settings → Subscription → "Manage subscription" opens Apple's subscription manager. Cancellation takes effect at the end of the current period — you keep Premium access until then.

Yes. Settings → "Restore purchases" pulls in any active Apple-ID-linked subscriptions and Lifetime entitlements.

All purchases are processed by Apple. Visit reportaproblem.apple.com to request a refund.

iPhone running iOS 26 or later. Apple Watch is recommended for HRV, VO₂max and overnight resting heart rate readings. iPad and Mac are not supported in v1.0.

Yes — every core feature (score, sub-scores, trends, interventions, labs, PDF report) runs on-device. The only network-dependent operation is StoreKit (purchases) and the contact form.

Not in v1.0. Both are on the v1.2 roadmap, contingent on the Go/No-Go review three months after launch.

Not in v1.0. iCloud / CloudKit sync is being considered for v1.1 — it depends on demand from beta users.

The headline feature is automatic intervention-effect analysis: before/after comparison (21 days vs 14 days), effect-size flagging (|d| > 0.5), and a notification three weeks after you start an intervention. Other v1.1 candidates include lab PDF OCR import and iCloud sync. Priorities will be set after launch based on user feedback.

Sextant Vitality intentionally avoids the streaks, the recovery-score arms race, and the optimised-athlete tone. The brand is calm, certain, understated — designed for men who want their numbers but don't want to feel like they're playing a game. If you want streaks, Whoop is great. If you want bearings, you're here.

Possibly. v1.0 is intentionally scoped to midlife men so the design, weights, and reference ranges are coherent for one persona. Expansion to other personas depends on the Go/No-Go review and user demand.