Comparison

FastFlow vs Pengu

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

Head to head
About

FastFlow

Features
Read full description

FastFlow is a lightweight fasting tracker and fasting timer for intermittent fasting plans like 16:8, 18:6, 20:4, and OMAD. It helps you start more easily, stay consistent, and better understand your own rhythm over time. With FastFlow, you can: - choose a common fasting plan or create your own custom schedule - start a fast in one tap and clearly track your duration and goal progress - receive start reminders, phase reminders, and goal reminders - keep a complete fasting history with add, edit, and delete support - review stats and weekly reports, including completions, streaks, and time trends - log weight alongside your fasting rhythm for longer-term reflection - generate share cards for completed fasts and weekly reports FastFlow is not a calorie-counting platform or a heavy social app. It is a calmer, lighter, and more reliable companion for building a fasting rhythm you can actually keep. Important: intermittent fasting is not suitable for everyone. If you are pregnant, breastfeeding, or have a medical condition or blood sugar concern, please consult a qualified healthcare professional first. Privacy Policy: https://fasting-nu.vercel.app/privacy Terms of Use: https://www.apple.com/legal/macapps/stdeula/

About

Pengu

Track your intermittent fasting and meals with a gentle approach. Features include fasting timers, one-photo meal logging with auto-detection, and calorie counting. Monitor your progress with a visual mascot and calendar view.

Highlights
  • Intermittent fasting timers (16:8, 18:6)
  • One-photo meal logging
  • Calorie and nutrition tracking
  • Penguin progress mascot
  • Auto-detected food menus
  • Calendar view of past data
Features
Read full description

Pengu: a gentle fasting, diet, and meal tracker. Intermittent fasting timers (16:8, 18:6), one-photo meal logging, and calorie tracking — all in one app. [Key features] • Pick a plan like 16:8 or 18:6 and start the timer with one tap • A penguin mascot shifts with your fasting progress, so you can see how it's going at a glance • Snap a food photo and Pengu auto-detects the menu and nutrition • When the result looks off, edit it by hand right away • Daily totals for calories, protein, carbs, and fat • Calendar view of your past fasts and meals • Available in English, Korean, Japanese, and Chinese [Pengu Pro] Unlimited photo analysis, full history, every fasting plan, and extra insights. Cancel anytime from your subscription settings. Take it lightly, keep it going — with Pengu. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://shore-clutch-a8c.notion.site/Privacy-Policy-36cb98f789b8807fa028f82bdb713cb5

Screenshots

FastFlow4 screens
Pengu4 screens

Verdict

The call

The clearest difference is ads: Pengu at none against FastFlow's shown. Pengu also leads on iOS requirement (15.1 vs 17.0). On price, update cadence, in-app purchases 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. FastFlow sells 2 in-app purchases, starting at $0.99 per month and Pengu sells 3 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

FastFlow ships an update every 5 days, Pengu every 9 days. The most recent releases landed on October 3, 2026 and October 12, 2026 respectively.

Scorecard2 real differences · 8 level
FastFlow versus Pengu: the parameters behind the verdict, then further details
ParameterFastFlowPengu
PriceFreeFree
Rating—5.0 (1 ratings) — better
Positive reviews—50.0% of reviews
Number of ratings—1 — better
Update frequencyEvery 5 days — betterEvery 9 days
AdsYesNo — better
In-app purchasesYesYes
Monetization—Freemium
DevicesiPhoneiPhone, iPod — better
Requires iOS17.015.1 — better
Further details — not scored
Size11 MB58 MB
Age rating4+4+
Developer浩铭 顾junhee cho

In-app purchases

2 purchases

FastFlow

Subscriptions2
  • FastFlow Pro Monthly$0.991 Month
  • FastFlow Pro Yearly$9.991 Year
3 purchases

Pengu

Subscriptions3
  • Pengu Pro Weekly$4.997 Days
  • Pengu Pro Monthly$5.991 Month
  • Pengu Pro Yearly3 Days trial$39.991 Year

Questions

Is FastFlow free?
FastFlow is free to download, with in-app purchases available.
Is Pengu free?
Pengu is free to download, with in-app purchases available.
Do FastFlow or Pengu have ads?
FastFlow shows ads; Pengu does not.
Which is updated more often, FastFlow or Pengu?
FastFlow ships an update every 5 days, and Pengu every 9 days. Most recently, FastFlow was updated on October 3, 2026 and Pengu on October 12, 2026.

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