Support & FAQ

Get help with Cardio Analytics. Frequently asked questions and contact information.

Frequently Asked Questions

How accurate is Apple Watch VO₂ Max?

Wrist-based VO₂ Max is an estimate that may differ from lab testing. Recent studies show non-trivial measurement error compared to gold-standard indirect calorimetry (PLOS ONE 2025). Cardio Analytics emphasizes trends and relative changes over time rather than absolute values. Focus on whether your VO₂ Max is improving or declining, not the specific number.

Does Cardio Analytics diagnose atrial fibrillation?

No. Cardio Analytics displays Apple Watch ECG classifications and AF episodes for you and your clinician to review, but it does not diagnose atrial fibrillation. While the Apple Heart Study demonstrated that smartwatch alerts can help identify AF (NEJM 2019), diagnosis requires clinical evaluation by a qualified healthcare provider. Always consult your doctor if you see irregular rhythm notifications or AF classifications.

Why are some metrics missing from my dashboard?

Cardio Analytics automatically hides metric cards when no data is available. Common reasons include: (1) Device limitations - SpO₂ requires Apple Watch Series 6 or later; mobility metrics require iPhone 8 or later with iOS 14+. (2) Regional restrictions - Some features may be unavailable in certain countries. (3) Insufficient data - Metrics appear once HealthKit has recorded at least one measurement. The app adapts to show only the metrics your devices can track.

How does Cardio Analytics protect my privacy?

All health data is processed and stored locally on your iPhone. There are no cloud servers, no data uploads, and no external transmission. You control HealthKit permissions granularly and can export reports only when you choose to share them. Read our full privacy policy.

Can I use Cardio Analytics with connected blood pressure monitors?

Yes! Any Bluetooth blood pressure cuff that syncs to Apple HealthKit (Omron, Withings, QardioArm, etc.) will automatically appear in Cardio Analytics. Manual entries in Apple Health also sync.

How accurate are Apple Watch heart rate measurements?

Apple Watch heart rate measurements are generally accurate for resting and walking HR. However, optical sensors can be affected by skin tone, tattoos, motion, and fit. For clinical decisions, discuss measurements with your clinician.

What blood pressure categories does Cardio Analytics use?

We use American Heart Association (AHA) categories: Normal (<120/<80), Elevated (120-129/<80), Stage 1 (130-139 or 80-89), Stage 2 (≥140 or ≥90). You can personalize thresholds based on your clinician's recommendations.

Can I export my data to share with my doctor?

Yes! Cardio Analytics generates professional PDF and CSV reports with all your cardiovascular metrics, medications, symptoms, and trends. Export and share via email, AirDrop, or any method you prefer.

Does Cardio Analytics require an internet connection?

No. All data processing happens locally on your device. Cardio Analytics works fully offline. Internet is only needed for downloading the app from the App Store.

What's the difference between SDNN and RMSSD for HRV?

SDNN (Standard Deviation of NN intervals) measures overall heart rate variability, reflecting total autonomic nervous system activity over longer periods. RMSSD (Root Mean Square of Successive Differences) measures short-term HRV and primarily reflects parasympathetic (vagal) tone. Both are valuable markers: SDNN shows general autonomic function, while RMSSD is more sensitive to acute stress and recovery status. Lower values of either metric may indicate increased stress or reduced cardiovascular health.

Can I track medications not in HealthKit?

Yes. Cardio Analytics allows manual medication logging even if you don't use HealthKit Medications. You can also sync medications from HealthKit if your pharmacy or clinician provides them.

Is Cardio Analytics a medical device?

No. Cardio Analytics is a wellness and fitness app. It does not diagnose, treat, cure, or prevent any disease. All metrics are for informational purposes. Always consult a qualified clinician for medical advice.

Contact Support

If you have questions not answered above, please contact us:

Email: info@onmedic.com

We typically respond within 1-2 business days.

Medical Disclaimer

Cardio Analytics does not provide medical diagnosis, treatment, or advice. All cardiovascular metrics are for informational and wellness purposes only.

Always consult a qualified healthcare provider for:

  • Medical diagnosis and treatment decisions
  • Interpretation of cardiovascular measurements
  • Personalized health targets and thresholds
  • Medication adjustments
  • Any symptoms or concerns about your health

In case of emergency: Call your local emergency services immediately. Do not rely on Cardio Analytics for emergency medical situations.

Start Tracking Your Heart Health

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