Comparison

Harmony vs Diary BFF

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

Head to head
About

Harmony

This app helps you understand and sync your lifestyle with your natural body rhythms. It offers personalized guidance for energy, meals, movement, and mindset based on your cycle phase. It also includes smart tracking, daily insights, and an AI assistant for daily organization and self-awareness.

Highlights
  • Cycle Syncing Guidance
  • Smart Cycle Tracking
  • Daily Insights & Rituals
  • AI Lifestyle Assistant
  • Partner Connection
  • Privacy-Focused Data
Read full description

More than a period tracker. Harmony helps you sync your lifestyle with your cycle. Your energy, meals, movement, and mindset, all in one place. Your body follows a unique rhythm that shapes how you feel, move, and think. Harmony helps you understand it and work with it, not against it. Most cycle apps track your period. Harmony helps you live better because of it. What Harmony offers: - Cycle Syncing Guidance Personalized tips for each phase of your cycle. What to eat, how to move, and how to recharge based on where you are right now. - Smart Cycle Tracking Log your period, symptoms, and mood. Get a clear view of your current phase and what's coming next. - Daily Insights & Rituals Meditations, journaling prompts, and mindset tips aligned with your natural rhythm. - AI Lifestyle Assistant Friendly, personalized guidance to help you stay organized and in tune with yourself every day. - Harmony Together Connect with your partner so they can better understand and support your cycle. - Your data stays yours. Built with privacy at its core. We never sell your data. Ever. Harmony is a lifestyle and wellness tool. It does not provide medical advice or diagnoses. Start with a free trial and find your rhythm. Web: https://harmony-cycle.app Terms of Use: https://legal.rocapine.com/terms Privacy Policy: https://legal.rocapine.com/privacy

About

Diary BFF

Features
Read full description

Most people quit journaling because nobody reads it. There is someone in this one. Diary BFF is a private night journal that writes back. You put down whatever your brain is doing at 2am; your diary BFF says one thing back — short, and only if it's worth saying — then leaves you alone so you can sleep. Some nights your head won't stop. You lie there going over the same thing, and the more you try to sleep the louder it gets. This is a place to say it to someone. Write what's in your head. It stays on the page, and your BFF stays quiet until you ask. A diary first; in the chat, you can talk it through. Not a coach — someone who remembers what you wrote last week. Your diary is locked with its own PIN — separate from the one on your phone. Not even an unlocked phone opens it. That's the point. WHAT IT'S LIKE Rather talk than type? In the chat, you can just say it. Voice, the Sunday letter, and export are all just ways of talking to your BFF and keeping what you said. Your diary BFF is not keeping score. There is no streak to keep and nothing to break, and writing four nights one week and none the next is not a failure this app will ever point out to you. Your entries live under your own account. Your diary is backed up every night, and you can export your diary, any time — exported backups can be locked too. Entries are not used to train AI. Kept a diary in another app? Bring your old entries along. They come over with up to 10 photos each. Deleted entries wait 30 days in Recently Deleted, in Settings, where you can restore them. Full version: up to 10 photos per entry. Writing stays free — typing is never metered. Your BFF's replies and the full Sunday letter come with the full version, which starts with a 14-day free trial. Cancel, and your diary still opens. SUBSCRIPTION Diary BFF Pro is an auto-renewing subscription. Both plans start with a 14-day free trial; if you don't cancel at least 24 hours before it ends, the subscription starts and renews automatically. Payment is charged to your Apple Account at confirmation of purchase. The subscription renews automatically unless it is turned off at least 24 hours before the end of the current period; your account is charged for renewal within 24 hours before the period ends. You can manage the subscription and turn off auto-renew in your Apple Account settings after purchase. Terms of Use (EULA): https://diarybff.app/terms/ Privacy Policy: https://diarybff.app/privacy/

Screenshots

Harmony4 screens
Diary BFF4 screens

Verdict

The call

The clearest difference is ads: Diary BFF at none against Harmony's shown. Diary BFF also leads on update cadence (every 3 days vs every 6 days). On price, in-app purchases, device support and iOS requirement 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. Harmony sells 13 in-app purchases, starting at $4.99 per 7 days and Diary BFF sells 2 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Harmony ships an update every 6 days, Diary BFF every 3 days. The most recent releases landed on October 28, 2026 and October 29, 2026 respectively.

Scorecard2 real differences · 8 level
Harmony versus Diary BFF: the parameters behind the verdict, then further details
ParameterHarmonyDiary BFF
PriceFreeFree
Rating4.7 (10K ratings) — better—
Positive reviews35.8% of reviews—
Number of ratings10K — better—
Update frequencyEvery 6 daysEvery 3 days — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhoneiPhone, iPod — better
Requires iOS16.415.0 — better
Further details — not scored
Size180 MB13 MB
Age rating4+12+
DeveloperRocapineBen Chao Chen

Bugs and requests

Harmony

Reported bugs

2 issues
  • Calendar issues with incorrect period dates
  • Inability to select accurate period dates

Requested features

3 requests
  • More community features
  • Longer meditation exercises
  • Additional recipes and meal plans

Diary BFF

Not enough reviews yet to summarise bugs or requests.

In-app purchases

13 purchases

Harmony

Subscriptions13
  • Premium Subscription$4.997 Days
  • Harmony Monthly Plan$9.991 Month
  • Monthly Subscription$14.991 Month
Show 10 more
  • Harmony Premium Pan$14.991 Month
  • Harmony Yearly Plan7 Days trial$34.991 Year
  • Yearly Premium1 Year trial$34.991 Year
  • Harmony Yearly Plan2 variants$34.991 Year
  • Harmony Premium7 Days trial$39.993 Months
  • Premium Subscription$39.996 Months
  • Yearly Subscription7 Days trial2 variants$49.991 Year
  • Yearly Subscription7 Days trial$59.991 Year
  • Harmony Yearly Plan7 Days trial$79.991 Year
  • Harmony Yearly Plan7 Days trial$89.991 Year
2 purchases

Diary BFF

Subscriptions2
  • Diary BFF Pro Monthly14 Days trial$9.991 Month
  • Diary BFF Pro Yearly14 Days trial$59.991 Year

Questions

Is Harmony free?
Harmony is free to download, with in-app purchases available.
Is Diary BFF free?
Diary BFF is free to download, with in-app purchases available.
Do Harmony or Diary BFF have ads?
Harmony shows ads; Diary BFF does not.
Which is updated more often, Harmony or Diary BFF?
Harmony ships an update every 6 days, and Diary BFF every 3 days. Most recently, Harmony was updated on October 28, 2026 and Diary BFF on October 29, 2026.

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