Comparison

Synca vs Rhythmus

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

Head to head
About

Synca

This app uses AI to help you plan your daily tasks and activities around your menstrual cycle. It provides personalized insights and suggestions for energy, focus, and mood based on your current cycle phase. Optimize your productivity and well-being by working with your body's natural rhythms.

Highlights
  • AI-powered cycle-aware task planning
  • Personalized daily insights based on cycle phase
  • Four cycle phases with identified strengths
  • Smart calendar with energy-based event tagging
  • Quick daily mood and energy tracking
  • Phase-matched workout and meal suggestions
  • Private data storage on device
Read full description

Synca helps you plan your days around your menstrual cycle, not against it. Powered by AI and backed by science. Your hormones affect your energy, focus, and mood every single day. Synca reads your cycle phase and tells you when to push hard, when to communicate, and when to rest. Stop guessing why some days feel harder than others. CYCLE-AWARE PLANNING Brain dump your tasks — Synca's AI sorts them into your day based on your current cycle phase and energy levels. The right task, at the right time, in the right phase. 4 PHASES, 4 SUPERPOWERS Menstrual, follicular, ovulatory, luteal — each phase brings different strengths. Synca color-codes your entire month so you always know what's coming and how to prepare. AI DAILY INSIGHTS Every morning, get a personalized insight based on where you are in your cycle. What to expect, what to prioritize, and how to make the most of your day. SMART CALENDAR Your events tagged with cycle-aware energy badges — "Peak performance", "Go gentle", "Deep focus." See your schedule through the lens of your biology. TRACK IN 10 SECONDS Log your mood, energy, and symptoms with a quick daily check-in. The more you track, the smarter Synca gets. MOVE & NOURISH Workout and meal suggestions matched to your phase. HIIT when you peak. Yoga when you rest. Iron-rich foods during menstrual. Complex carbs in luteal. Science-backed, not generic. PREDICTIONS THAT LEARN Period predictions, cycle trends, and personal patterns and all getting smarter with every cycle you complete. PRIVATE BY DESIGN All health data is stored locally on your device. No account required to get started. No data sold. No third-party trackers. Your body, your data. Built by a woman, for women. Synca exists because your productivity tools should understand your biology. Full access available with a 1 month free trial subscription. Terms of Use: https://hellosynca.co/terms

About

Rhythmus

Features
Read full description

Rhythmus is a period tracker with a cycle calendar — plus a nutrition and training plan that changes with your cycle. WHAT RHYTHMUS DOES • Cycle and period calendar: log your period, see your cycle day and phase at a glance, with estimated ovulation and fertile window • Nutrition plan: meals and nutrients matched to your current phase – omnivore, vegetarian, vegan – with a shopping list • Training plan: workouts scaled to your intensity and training days, logged set by set • Supplements: which nutrients matter in which phase • Daily energy check-in: feeling low, and the app suggests a gentler session • Weekly overview, symptom diary, cycle statistics from your own history WHO IT IS FOR For women who train and notice that the same session feels easy one week and impossible the next. Menstruation, follicular phase, ovulation and the luteal phase each ask for something different — Rhythmus takes that into account. NO ACCOUNT, NO TRACKING No sign-up, no registration, no ads, no subscriptions, no in-app purchases. Everything you enter stays on your device and is sent nowhere. The app works fully offline. From Settings you can export a backup at any time and restore it on another device. WITH SOURCES Every health statement in the app comes with a citation you can tap — straight to the study or fact sheet. Among others from the Journal of the International Society of Sports Nutrition, the Journal of Medical Internet Research and the National Institutes of Health. Available in German, English and Spanish. Rhythmus is a free passion project. Note: Rhythmus is not a medical device, not a contraception method, and does not replace medical advice.

Screenshots

Synca4 screens
Rhythmus4 screens

Verdict

The call

The clearest difference is in-app purchases: Rhythmus at none against Synca's 2. Rhythmus also leads on update cadence (every 3 days vs every 2 weeks) and iOS requirement (15.0 vs 17.0). 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. Synca sells 2 in-app purchases, starting at $4.99 per month. Rhythmus asks for nothing beyond the download.

UpkeepUpdate frequency

Synca ships an update every 2 weeks, Rhythmus every 3 days. The most recent releases landed on October 31, 2026 and November 6, 2026 respectively.

Scorecard3 real differences · 7 level
Synca versus Rhythmus: the parameters behind the verdict, then further details
ParameterSyncaRhythmus
PriceFreeFree
Rating5.0 (2 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings2 — better—
Update frequencyEvery 2 weeksEvery 3 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationSubscription—
DevicesiPhoneiPhone, iPod — better
Requires iOS17.015.0 — better
Further details — not scored
Size25 MB21 MB
Age rating4+4+
DeveloperBurcu IbiciogluPatrick Sarpen

In-app purchases

2 purchases

Synca

Subscriptions2
  • Synca AI$4.991 Month
  • Synca AI7 Days trial$24.991 Year
None

Rhythmus

No in-app purchases

Questions

Is Synca free?
Synca is free to download, with in-app purchases available.
Is Rhythmus free?
Rhythmus is free to download, with no in-app purchases.
Do Synca or Rhythmus have ads?
Neither Synca nor Rhythmus shows ads.
Which is updated more often, Synca or Rhythmus?
Synca ships an update every 2 weeks, and Rhythmus every 3 days. Most recently, Synca was updated on October 31, 2026 and Rhythmus on November 6, 2026.

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