Comparison

Fast Slow vs Fasting Tracker

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

Head to head
About

Fast Slow

Understand your body's metabolic changes during fasting with a visual timeline. This free app guides you through different fasting zones, from digestion to deep ketosis, and offers customizable schedules and smart notifications. It provides stats, streaks, and widgets for easy progress tracking.

Highlights
  • Fasting timer with visual timeline
  • 6 customizable fasting schedules
  • 5 distinct fasting zones explained
  • Smart notifications for fasting windows
  • Stats, streaks, and trends tracking
  • Home and Lock Screen widgets
  • Siri Shortcuts integration
Features
Read full description

See what happens inside your body as you fast. Fast Slow walks you through 5 fasting zones, from digestion through fat burning to deep ketosis, so you understand what every hour of your fast is doing. 100% free. Every feature. No ads. No paywalls. No trackers. Free forever. WHAT MAKES FAST SLOW DIFFERENT Most fasting apps just count down a timer. Fast Slow shows you what's actually happening in your body at each stage: - Anabolic (0-4h): Digesting and storing nutrients - Catabolic (4-8h): Tapping into energy reserves - Fat Burning (8-12h): The metabolic switch - Ketosis (12-16h): Ketones and cellular cleanup - Deep Ketosis (16h+): Deep cellular renewal Tap any zone to learn more about the science behind it. 100% FREE. EVERY FEATURE INCLUDED. No premium tier. No trial that expires. No paywall gates. Every feature in Fast Slow is yours from day one: - All 6 fasting schedules - All stats, streaks, and trends - All widgets (Home Screen and Lock Screen) - All notifications - Siri Shortcuts - iCloud sync - Data export Everything free. No catches. FEATURES Fasting Timer One tap to start. One tap to stop. A visual timeline shows where you are, what zone you're in, and what comes next. 6 Fasting Schedules 12:12 for beginners, 14:10, 16:8 (the most popular), 18:6, 20:4, and OMAD (one meal a day) for experienced fasters. Visual Timeline Color-coded timeline of your fasting and eating windows. Plan meals, training, and recovery at a glance. Smart Notifications 7 notification types: goal reached, halfway there, one hour left, eating window alerts, and a custom last meal reminder. Nudges, not nags. Stats & Streaks Total fasts, average duration, personal records, weekly trends, and a monthly fasting calendar. Small wins add up. Widgets Home Screen and Lock Screen widgets with progress rings, timelines, and live timers. Check your fast without opening the app. Siri Shortcuts "Hey Siri, start my fast." Start, stop, and check your fasting status hands-free. AI-Powered Greetings On supported devices, Apple Intelligence creates personalized messages based on your fasting progress, streak, and time of day. iCloud Sync Your fasting data syncs automatically across all your devices. Data You Own Export your fasting history as JSON. Delete everything with one tap. Your data, your choice. DESIGNED FOR REAL LIFE Pick a schedule, adjust as needed, and let Fast Slow handle the timing. New to fasting or already have a routine, it works either way. Structure when you want it, out of the way when you don't. Built by one developer who fasts every day. No corporate agenda. No growth hacking. A well-made tool that respects your time and your data. RESPONSIBLE APPROACH Intermittent fasting can support weight management, energy, and focus, but results vary. Fast Slow provides tools and information, not medical advice. If you have health conditions, are pregnant, or have a history of eating disorders, please talk to a healthcare professional before starting.

About

Fasting Tracker

Easily track your fasting periods with a simple, one-tap interface. Monitor your progress through different fasting stages in real-time and receive notifications upon completion. Visualize your consistency with a progress calendar and track your health stats and streaks.

Highlights
  • One-tap fasting start
  • Real-time fasting stage tracking
  • Multiple fasting protocols
  • Progress calendar
  • Health stats and streak tracking
  • Dark and light mode
Features
Read full description

Freedom Fast is a clean, simple fasting tracker designed to help you stay consistent and build lasting habits. Start a fast with one tap. Watch your progress in real time as you move through each fasting stage — from fat burning to deep ketosis. Get notified the moment your fast is complete. FEATURES • Timer with live fasting stage tracking • Multiple fasting protocols (16:8, 18:6, 24h, and more) • Progress calendar to visualize your consistency • Health stats and streak tracking • Dark and light mode • Supports multiple languages Freedom Fast is free to use. If you find it helpful, there's an optional tip jar — no subscriptions, no paywalls.

Screenshots

Fast Slow4 screens
Fasting Tracker4 screens

Verdict

The call

The clearest difference is monetization model: Fast Slow at free against Fasting Tracker's free with in-app purchases. Fasting Tracker's advantage is iOS requirement (15.1 vs 18.0). On price, rating, review sentiment and ratings volume 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. Fast Slow sells 4 in-app purchases, starting at $1.99 per 7 days and Fasting Tracker sells 6 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for Fast Slow against 4.9 for Fasting Tracker. Both are backed by a comparable volume of ratings — 22 and 21 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

Fast Slow ships an update fortnightly, Fasting Tracker every 2 weeks. The most recent releases landed on September 13, 2026 and September 19, 2026 respectively.

Scorecard2 real differences · 8 level
Fast Slow versus Fasting Tracker: the parameters behind the verdict, then further details
ParameterFast SlowFasting Tracker
PriceFreeFree
Rating5.0 (22 ratings) — better4.9 (21 ratings)
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings22 — better21
Update frequencyFortnightlyEvery 2 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhoneiPhone, iPod — better
Requires iOS18.015.1 — better
Further details — not scored
Size19 MB37 MB
Age rating4+4+
DeveloperZan CerneJosef Reuben Encinares

Customer experience

Fast Slow

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Fasting Tracker

Written reviews9 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

4 purchases

Fast Slow

Subscriptions2
  • Legacy$1.997 Days
  • Legacy - Yearly3 Days trial$12.991 Year
One-time2
  • Buy Me a Coffee$2.99
  • You're Amazing$9.99
6 purchases

Fasting Tracker

One-time6
  • A Kind Nudge$0.99
  • Buy Me A Cofee$1.99
  • A Generous Gift$2.99
Show 3 more
  • Buy Me a Meal$4.99
  • You're Amazing$9.99
  • Full Supporter$19.99

Questions

Is Fast Slow free?
Fast Slow is free to download, with in-app purchases available.
Is Fasting Tracker free?
Fasting Tracker is free to download, with in-app purchases available.
Which has better reviews, Fast Slow or Fasting Tracker?
Fast Slow is rated higher. Fast Slow averages 5.0 out of 5 from 22 ratings, while Fasting Tracker averages 4.9 from 21 ratings.
Do Fast Slow or Fasting Tracker have ads?
Neither Fast Slow nor Fasting Tracker shows ads.
Which is updated more often, Fast Slow or Fasting Tracker?
Fast Slow ships an update fortnightly, and Fasting Tracker every 2 weeks. Most recently, Fast Slow was updated on September 13, 2026 and Fasting Tracker on September 19, 2026.

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