HRV Mood Tracker for iPhone
See your mood before it arrives.
MoodQuad is the mood tracking app that reads your heart. It connects your heart rate, HRV, and sleep to a well-established psychological model — and forecasts your emotional patterns days before you feel them.
Free to start · No account · 100% on-device · Built by a board-certified physician
Four states. Two dimensions. One honest picture.
A 1-to-10 mood scale flattens your emotional life. MoodQuad maps it across pleasantness and energy — the circumplex model used in psychology research for decades.
Stressed
Racing heart, low HRV, restless sleep. MoodQuad often sees this state building in your physiology before you name it.
Energized
Motivated, focused, alive. Learn which days, sleep patterns, and habits reliably put you here — and get more of them.
Low Mood
Flat, drained, withdrawn. Spot the repeating sequences that lead here, so you can prepare instead of just react.
Calm
Rested and at ease — typically your highest-HRV state. See what your body looks like when things are going right.
How mood forecasting works
Your physiology shifts before your mood does. MoodQuad notices.
Your body knows first
Optionally connect Apple Health. MoodQuad reads heart rate, heart rate variability (HRV), and sleep from your Apple Watch, Whoop, or other wearable — processed entirely on your iPhone.
Drop a dot on the Mood Map
Capture how you feel in seconds: one dot for pleasantness and energy, plus optional notes and tags. No essays, no friction, no judgment.
See what's coming
As MoodQuad learns your patterns — time of day, day of week, HRV and sleep correlations — it surfaces likely emotional trends in the days ahead, so you can prepare instead of react.
Inside the app
Designed to be glanceable, private, and genuinely useful — not another feed to maintain.
THE MOOD MAP
MOOD FORECAST
HRV & SLEEP INSIGHTS
PATTERNS
HISTORY & TAGS
PRIVATE EXPORT
Guides: understand your heart, understand your mood
Physician-written answers to the questions your Apple Watch raises but never answers.
Why is my HRV so low? What Apple Watch doesn't tell you
Stress, sleep, alcohol, training — and why a single low reading almost never means what you fear it means.
Read the guide → HRVWhat is a good HRV? Normal ranges by age (and why they barely matter)
Typical values, why comparing yourself to others misleads you, and the number that actually matters: your baseline.
Read the guide → HRVHow to improve your HRV: what actually works
Sleep, breathing, alcohol, exercise timing — an evidence-based look at what moves HRV and what's noise.
Read the guide → ScienceHRV and mood: the science of how your heart reflects your emotions
Why heart rate variability is the most useful biometric for emotional state — and how to actually use it.
Read the guide → How-toMood tracking with Apple Watch: the complete setup guide
Your watch already collects the data. Here's how to turn heart rate, HRV, and sleep into real emotional insight.
Read the guide → MoodMood forecasting: can you really predict how you'll feel?
What the research says about anticipating emotional patterns — and how forecasting changes how you plan your life.
Read the guide → ScienceThe circumplex model of emotion, explained simply
The two-dimensional map of feeling that psychology has used since 1980 — and why it beats a 1-to-10 scale.
Read the guide → CompareThe best mood tracker apps for iPhone: an honest guide
What separates a mood tracker you'll still use in month three from one you'll abandon in week one.
Read the guide →Free to start. Fairly priced to keep.
No account. No ads. No data harvesting. Just a tool that pays for itself in self-knowledge.
Free
$0
- Manual tracking on the Mood Map
- 7-day history
- Basic insights
Premium Annual
$39.99/YEAR · SAVE 33%
- Mood forecasting
- Full HRV + heart rate integration
- Unlimited history & advanced patterns
- Export to PDF, CSV, JSON
- 7-day free trial · also $4.99/month
Lifetime
$69.99· ONE-TIME
- Everything in Premium
- Pay once, keep forever
- No subscription
Frequently asked questions
How does MoodQuad forecast my mood?
MoodQuad connects your heart rate, heart rate variability (HRV), and sleep data from Apple Health to the moods you log on the Mood Map. As it learns your personal patterns, it surfaces likely emotional trends in the days ahead — for self-reflection, not clinical prediction. Learn more about mood forecasting →
Why is my HRV so low on Apple Watch?
Usually stress, poor sleep, illness, alcohol, or hard training — and Apple Watch readings vary a lot by time of day. What matters is your trend against your own baseline, not any single number. Learn why your HRV is low →
What is a good HRV?
There's no universal "good" HRV — typical adult values fall roughly between 20 and 75 ms and vary with age, sex, and fitness. The meaningful signal is how your HRV moves relative to your own baseline. Learn what a good HRV is →
Does MoodQuad work with Apple Watch?
Yes. MoodQuad reads heart rate, HRV, and sleep recorded by your Apple Watch — or any wearable that writes to Apple Health, like Whoop — through an optional integration. You can also use it with no wearable at all. Learn how to track mood with Apple Watch →
What is the Mood Map?
A two-dimensional way to log emotion based on the circumplex model: pleasantness on one axis, energy on the other. Your moods organize into four states — Energized, Stressed, Low Mood, and Calm. Learn about the model behind it →
Is my mood data private?
Yes. No account required, no tracking, no third-party analytics — all processing happens on your device, and you can export your history anytime as PDF, CSV, or JSON.
How much does MoodQuad cost?
Free to start. Premium — forecasting, unlimited history, full HRV integration, and export — is $4.99/month or $39.99/year after a 7-day free trial, or $69.99 once for lifetime access.
Is MoodQuad a medical device?
No. MoodQuad is a self-reflection tool built by a board-certified physician. It does not provide medical advice, diagnosis, or treatment. If you're experiencing a mental health crisis, please contact a qualified professional or local emergency services.
Your heart has been keeping notes. Start reading them.
Free to start. Private by design. Forecasting in your pocket after a week of dots.
Get MoodQuad for iPhone