A daily score from 0 to 100 that represents your morning condition. It's calculated from three factors:

• Wake-up HRV (50%): Heart rate variability measured during sleep, reflecting recovery quality
• Resting Heart Rate (25%): Lower is generally better
• Sleep Duration (25%): 7-8 hours is optimal

The score is personalized to your own baseline using your past 30 days of data (works with 3+ days, accuracy improves with 14+ days).

Design philosophy: Your "typical day" scores around 75 (Good). The goal isn't 100 — it's to maintain your own healthy rhythm.

Scores are grouped into four levels:

• 80–100 Excellent: Especially well-recovered for you. A day to take on bigger challenges
• 60–79 Good: Your typical condition. Most days will land here
• 40–59 Fair: Some fatigue may be lingering. Don't push too hard
• 0–39 Poor: Significantly under-recovered. Prioritize rest

Don't aim for 100 every day. Steadily staying in the 60–80 range is the real goal. On low days, one minute of breathing is enough to reset.

Yes, that's completely normal. Your score fluctuates based on sleep quality, previous day's activity, stress levels, alcohol consumption, and more. What matters is the trend over a week, not a single day's number. Check the 7-day chart in the Condition tab to see your trends.

The Trends section of the Condition tab lets you switch between 7d and 8w. Choosing 8w shows how four measures have moved over the past eight weeks: wake-up HRV, resting heart rate, sleep duration, and respiratory rate.

You can usually sense a single day or a single week. What is hard to notice is a change that unfolds slowly over weeks. This view exists to make that visible.

The chart has two layers. The faint dots are your daily readings exactly as recorded; the solid line is a 7-day median. Wake-up HRV can swing more than 20% from day to day, so the dots alone would bury any longer movement — while the line alone would hide how much things actually vary. Showing both keeps everything visible.

A single line such as "Your wake-up HRV has been gradually declining over the past 8 weeks" appears only when the movement is clear. If nothing appears, no clear trend was found.

The message makes no judgement about good or bad. It describes how your recorded numbers moved. The same pattern can come from the season, activity, alcohol, travel, menstrual cycle, or a change in how you wear your Apple Watch.

What this feature cannot find (stated plainly):

• Very slow or very small changes stay buried in normal day-to-day variation
• Periods with few recorded days cannot be assessed (you'll see "too few readings to show a trend")
• No message does not mean nothing changed

If you have any concern about your health, please consult a medical professional regardless of what these numbers show.

Under wake-up HRV, resting heart rate, and sleep on the Condition tab, you'll see how much that measure moved over the past 8 weeks — the difference between the start and end of the trend line on the 8-week chart.

It is a number rather than an arrow because the number is a record, and an arrow would be an interpretation. It makes no judgement about good or bad.

• It is highlighted only when the trend is clear
• Nothing is shown for a measure with too few readings (this does not mean nothing changed)

From v1.9, the wake-up HRV trend uses values measured during that night's sleep (or morning values when there is no sleep record), so numbers may differ slightly from earlier versions.

This appears when the Apple Watch model that measured your HRV changed within the 8 weeks.

Different models measure differently — Series 12, for example, samples HRV far more often than earlier models. So an 8-week trend that spans an upgrade mixes in the difference between instruments, not a change in your body.

During this time, trend emphasis (the one-line message and highlight) and the "8w ±" line under each number are paused. The charts and daily numbers remain. Once 8 weeks have been recorded on the new Watch, the usual display returns.

If you alternate between two Apple Watches on different days, this message may also appear.

From the morning condition notification you can log Heavy / Usual / Fresh with one tap, without opening the app. If you miss the notification, you can also log it from the Condition tab or your Apple Watch.

Your answer appears beside that day's numbers in the daily list. Since v1.8, a "How you felt vs. the numbers" block also counts the days over the past 12 weeks when the two matched or sat apart (see the next item). Neither one passes judgement — they only place the records side by side.

Answers are stored in iCloud and shared between iPhone and Apple Watch. Logging is entirely optional — skipping it affects nothing else.

It appears below the daily list on the Condition tab. Looking at the past 12 weeks, on days where both a morning check-in and a score were recorded, it counts the days that matched and the days that were apart.

• Matched: both how you felt and your numbers were high for you (or both were low for you)
• Apart: you felt Fresh but your numbers were low for you, or you felt Heavy but your numbers were high for you

"High" and "low" are not general benchmarks — they mean where that day sits within your own 12 weeks of records. Days you answered Usual sit in the middle and are not counted either way.

Apart days are listed with their dates, along with the measure that stood out most that day (such as wake-up HRV). Neither one is the right answer. How you feel and what your body records were never expected to line up perfectly, and having some apart days is normal. Everyone has days of feeling fine on low numbers, and days of feeling heavy on high ones.

This block only counts days. It never concludes anything about you, such as whether you notice your own state. It stays hidden until 14 days of both records exist (until then it says that more records are needed).

• iPhone: iOS 17.0 or later
• Apple Watch: watchOS 10.0 or later

HRV Flow sends three types of notifications:

• Morning condition: Your condition score and day-over-day comparison upon waking
• Stress alerts: When Apple Watch detects a drop in HRV
• Scheduled reminders: Breathing exercise reminders at your chosen times

Notifications are automatically suppressed during sleep. Morning condition alerts can be toggled on/off and the notification time can be changed in the Settings tab.

• Beginners: Start with "Simple Deep Breathing"
• Feeling stressed: "4-7-8 Breathing" or "Physiological Sigh" work well
• Improving focus: Try "Box Breathing"
• Improving HRV: "Coherent Breathing" is scientifically recommended
• Better sleep: Try "Sleep Breathing"
• Acute stress: "SOS Breathing" helps you calm down quickly

Yes — on iPhone, adjust it right before you start.

• Length: choose Default / ~1 min / ~3 min / ~5 min (the cycle count adjusts automatically)
• Rhythm: tune the inhale / hold / exhale seconds individually

Rhythm changes apply to that session only and aren't saved (reopening a pattern returns it to its default rhythm). Apple Watch stays focused on a quick, glanceable session, so this customization lives on iPhone.

Yes. A calm voice leads your breathing (available in Japanese and English).

• Phase cues (breathe in / hold / breathe out)
• Gentle hints ("let your shoulders drop," etc. — the same text shown on screen)
• Start and finish prompts

The audio is bundled with the app, so it plays offline with no network needed, and it's private. To avoid being chatty, the guide alternates between cues and hints.

Turning it on/off: on iPhone, from the pre-session screen; on Apple Watch, from the "Guidance" section of the breathing list. It's off by default (opt-in).

Yes. In the "Guidance" section at the bottom of the breathing list on Apple Watch, you can toggle each one independently.

• Voice: on/off (off by default)
• Haptics: on/off (on by default) — the vibration feedback during breathing

Turn voice off in quiet places, or keep only haptics before bed — whatever fits the moment.

Yes. You can display real-time HRV values and stress levels on your Apple Watch face. Circular, rectangular, and inline complications are supported.

Method 1: From Apple Watch

Method 2: From iPhone Watch app

Yes. Breathing sessions completed on Apple Watch are automatically synced to your iPhone within minutes. They will be reflected in the Habits tab for streak tracking and statistics.

HRV Flow is designed to minimize battery consumption.

• HRV monitoring: Simply receives data from Apple Watch's regular HRV measurements (every 10-30 minutes) — no additional sensor activity
• Complications: Event-driven updates only when new HRV data arrives
• During breathing sessions: Runs as a workout session, using battery similar to any workout app

Under normal use, the impact on Apple Watch's daily battery life is minimal.

HRV Flow calculates a "Personal Baseline" from your historical HRV data and compares your current HRV against it to assess stress in 4 levels:

• 😌 Relaxed: HRV is above your baseline
• 🟢 Normal: HRV is near your baseline
• 🟡 Elevated: HRV is below your baseline
• 🔴 High: HRV is significantly below your baseline

Time-of-day and day-of-week patterns are also considered, so the same HRV value may receive different assessments in the morning versus evening.

The personal baseline is calculated on your iPhone and synced to Apple Watch via iCloud. If it's not syncing:

• Check iPhone Settings → Notifications → HRV Flow is enabled
• Check Apple Watch Settings → Notifications → HRV Flow is enabled
• Make sure Focus Mode or Do Not Disturb is not active
• Confirm your Apple Watch is being worn and collecting HRV data

• Verify HealthKit permissions: iPhone Settings → Health → Data Access & Devices → HRV Flow
• Make sure your Apple Watch fits snugly on your wrist
• HRV data is measured automatically by Apple Watch (typically every 10-30 minutes)

During breathing exercises, a workout session keeps the app active. However, screen behavior depends on your Apple Watch model:

• Series 5 and later (Always On Display): The screen dims when you lower your wrist but remains visible
• SE / Series 4 and earlier (no Always On Display): The screen turns off when you lower your wrist. Raise your wrist or tap the screen to wake it

In both cases, haptic (vibration) guidance continues even when the screen is off. You can follow the breathing rhythm by vibration alone without watching the screen.

If a status code appears on the result screen, refer to the guide below:

W-AUTH (Workout write permission not granted)

W-START (Could not start workout session)

• Restart your Apple Watch and try again
• Make sure no other workouts are currently running

W-HR (Heart rate not detected)

• Make sure your Apple Watch fits snugly on your wrist
• Clean the back of the Watch (sensor area) if needed
• Very short sessions (e.g., Quick 3-0-3) may finish before the heart rate sensor fully starts. Try a longer pattern

W-REQ (Permission check failed)

• Restart your Apple Watch and try again

• Make sure both devices are signed in to the same iCloud account
• Confirm both devices are connected to the internet (Wi-Fi or mobile data)
• Check that workout reading and writing are enabled: iPhone Settings → Health → Data Access & Devices → HRV Flow
• Opening the iPhone app will automatically import any unsynced sessions