DEEP turns your Apple Watch into a comprehensive sleep lab. Every night, DEEP captures five biometric signals — HRV, heart rate, respiratory rate, SpO2, and sleep stages — and synthesizes them into a readiness score from 0 to 100 so you know exactly how recovered you are each morning.
DEEP tracks five core sleep metrics every night: heart rate variability (HRV), resting heart rate, respiratory rate, blood oxygen saturation (SpO2), and full sleep stage breakdowns including REM, deep, core, and awake time.
All data flows through Apple Health integration, meaning DEEP reads sensor data captured by Apple Watch (Series 4 and later) without requiring any additional hardware. Here is a breakdown of each metric and what it tells you:
| Metric | Source | What It Reveals |
|---|---|---|
| HRV (ms) | Apple Watch overnight samples | Autonomic nervous system recovery; higher is generally better |
| Resting Heart Rate (bpm) | Apple Watch sleep samples | Cardiovascular recovery; lower at rest indicates better fitness |
| Respiratory Rate (brpm) | Apple Watch sleep analysis | Breathing regularity; spikes may indicate illness or stress |
| SpO2 (%) | Apple Watch blood oxygen sensor | Blood oxygen saturation; normal range is 95-100% |
| Sleep Stages | Apple Watch sleep algorithm | Time in REM, deep, core, and awake phases |
DEEP calculates a readiness score from 0 to 100 using data from the last 24 hours, comparing each biometric against your personal rolling baseline to determine how recovered you are.
Rather than using population averages, DEEP builds individual baselines over time. Your HRV, resting heart rate, and respiratory rate are compared against your own historical norms. A readiness score of 80+ suggests you are well-recovered and ready for intense training, while a score below 50 indicates you should prioritize rest or light activity.
The readiness score also feeds into DEEP's AI coach, which cross-references your sleep quality with your training load and nutrition data to make personalized recommendations — something standalone sleep trackers cannot do.
Apple Watch sleep stage detection has been validated in peer-reviewed research to achieve approximately 78% agreement with clinical polysomnography, and DEEP enhances the raw data by adding trend analysis and cross-domain context.
DEEP does not replace the Apple Watch sleep algorithm — it reads the data Apple Health provides and layers additional analysis on top. This includes:
DEEP is the only iOS app that connects sleep biometrics directly to workout readiness and nutrition tracking in a single platform, eliminating the need for separate sleep, fitness, and diet apps.
| Feature | DEEP | Standalone Sleep Apps | Whoop/Oura |
|---|---|---|---|
| HRV Tracking | Yes (Apple Watch) | Varies | Yes (proprietary hardware) |
| Sleep Stages | Yes | Yes | Yes |
| Readiness Score | 0-100 scale | No | Yes |
| Workout Integration | 1,800+ exercise library | No | Limited |
| Nutrition Tracking | Full macro tracking + barcode | No | No |
| AI Cross-Domain Insights | Yes | No | No |
| Additional Hardware Required | No (Apple Watch only) | No | Yes ($299+ band/ring) |
| Pricing | Free tier / $14.99/mo / $99.99/yr | $4-10/mo | $30/mo (Whoop) |
DEEP sleep tracking works with Apple Watch Series 4 and later, with full SpO2 support on Series 6 and later. All sleep stage data and HRV readings require watchOS 9 or newer. DEEP reads and writes data through Apple Health, so no companion watch app is needed — just wear your Apple Watch to bed and DEEP handles the rest.
Yes. DEEP's AI coach analyzes your sleep trends alongside training and nutrition patterns to surface actionable insights — such as how late workouts or high caffeine intake correlate with lower HRV and disrupted sleep stages.
Because DEEP tracks sleep, exercise, and nutrition in one app, it can identify connections that siloed apps miss. For example, DEEP might notice that your deep sleep drops on days when you train after 8 PM, or that your HRV improves on days when your protein intake exceeds 1g per pound of bodyweight. These cross-domain insights are generated by the AI coach and presented as simple, personalized recommendations.