Comparison

Red Diary vs Quantum Self

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Red Diary

This app analyzes your symptoms, mood, energy, sleep, and activity to provide personalized insights and daily guidance tailored to your cycle phases. It offers a body weather forecast and smart recommendations for exercise, nutrition, and self-care.

Highlights
  • Personalized cycle insights
  • Smart daily guidance
  • Body weather forecast
  • Cycle tracking modes (fertility, pregnancy, birth control)
  • Symptom and mood logging
  • HealthKit integration
  • Apple Watch companion app
Features
Read full description

A period and cycle tracker that keeps your data on your phone. No account. No cloud. No tracking. No ads. Most period apps send your most private information to their servers. Red Diary doesn't have servers. Free to track your cycle, log symptoms, and get predictions — no trial, no card, no expiry. Premium unlocks the fertility, pregnancy, and insight modes. PRIVATE BY DESIGN Your cycle history, symptoms, and intimate details never leave your device. There is no account to create, no server to breach, and no company reading your data. Export anytime for a doctor's visit or your own backup — it's your information. BUILT FOR REAL CYCLES, NOT AVERAGE ONES Most trackers assume a textbook 28 days and get confused when yours doesn't cooperate. Red Diary reads each cycle on its own terms, so irregular, long, short, and changing cycles are understood instead of flagged as wrong. BODY WEATHER Your own forecast, built from your own logs. Red Diary looks for patterns across your history and tells you what today has tended to look like for you — sunny, clear, mixed, overcast, or stormy. If it doesn't have enough history to say something true, it tells you that instead of guessing. WHAT SHOULD I DO TODAY? Every time you open the app, you get an answer. Phase-aware guidance for movement, food, and rest that shifts as your body does. FOUR MODES Track My Cycle — phase-by-phase analytics and predictions Trying to Conceive — fertile window, peak day, cycle health, and support through the two-week wait Avoid Pregnancy — honest fertility status, including the days it can't be certain about I'm Pregnant — 40 weeks of content, kick counter, appointments, and trimester insights Switch whenever life changes. The app changes with you. A CALENDAR THAT ACTUALLY WORKS Start and end your period with one tap, right from the calendar. Backdate cycles you missed. Log intercourse. See period, predicted, fertile, and logged days at a glance — with moon phases, if you like tracking alongside them. WHY YOU FEEL LIKE THIS Log symptoms, mood, sleep, temperature, and more. Red Diary finds what repeats across your cycles and explains what's behind it, instead of just recording it. SHARE HOW YOU FEEL Send a phase-aware note to a partner, a friend, or your birth control buddy through iMessage, WhatsApp, or anywhere else. No accounts, on either end. ON YOUR WRIST Cycle day, phase, and progress ring on your watch face in phase-matched colors. Start or end your period, log your mood, and get guidance without reaching for your phone. APPLE HEALTH Steps, calories, exercise, and sleep flow in automatically. See how your energy and activity really shift across your cycle — no extra logging. BIRTH CONTROL REMINDERS Pill, patch, ring, shot, IUD, or implant. On-time reminders, streak tracking, and insights that adapt to your method. WHAT'S PREMIUM Trying to Conceive, Avoid Pregnancy, and Pregnancy modes, Body Weather, full cycle insights, fertility analytics, and mood sharing. Cycle tracking, logging, predictions, calendar, and birth control reminders are free and stay free. Privacy Policy: https://dormeusapps.com/reddiary-privacy.html Terms of Use: https://dormeusapps.com/reddiary-terms.html

About

Quantum Self

Features
Read full description

Quantum Self helps you stop waiting to become your next version and start living as them now. Start with the free 3-Day Quantum Self Challenge, guided by Nate Carter: - A short daily video lesson for each day - Guided practice and activation audio - A daily checklist and habit tracker to build your new routine - A journal with prompts to name, question and replace old beliefs - Progress tracking to see your shift over time - Your birth chart in both Tropical / Classic 12 and True Sidereal (13-Signs) Ready to go deeper? Explore The Quantum Leap 1:1™, Nate's 8-week private coaching for creators, coaches and healers, and apply right inside the app. Coaching clients get a private dashboard with their session schedule, journey map, action steps and direct chat with Nate.

Screenshots

Red Diary4 screens
Quantum Self4 screens

Verdict

The call

The clearest difference is in-app purchases: Quantum Self at none against Red Diary's 2. Quantum Self also leads on iOS requirement (15.1 vs 17.6). On price, ads and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Red Diary sells 2 in-app purchases, starting at $0.99 per month. Quantum Self asks for nothing beyond the download.

Scorecard2 real differences · 8 level
Red Diary versus Quantum Self: the parameters behind the verdict, then further details
ParameterRed DiaryQuantum Self
PriceFreeFree
Rating5.0 (9 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings9 — better—
Update frequencyEvery 3 days—
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
DevicesiPhone, Apple WatchiPhone, iPad, iPod — better
Requires iOS17.615.1 — better
Further details — not scored
Size8 MB139 MB
Age rating12+4+
DeveloperRUBINS DORMEUSNathan Carter

In-app purchases

2 purchases

Red Diary

Subscriptions2
  • Premium Monthly7 Days trial$0.991 Month
  • Premium Annual$4.991 Year
None

Quantum Self

No in-app purchases

Questions

Is Red Diary free?
Red Diary is free to download, with in-app purchases available.
Is Quantum Self free?
Quantum Self is free to download, with no in-app purchases.
Do Red Diary or Quantum Self have ads?
Neither Red Diary nor Quantum Self shows ads.

Other comparisons