Comparison

Just Fast vs Simple Fasting

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

Head to head
About

Just Fast

This app tracks both your fasting periods and your eating windows, offering a unique dual-countdown feature. It visualizes metabolic phases like fat burning and ketosis, supports various fasting methods, and provides insights into your progress. It's designed to be user-friendly and privacy-conscious, working entirely offline.

Highlights
  • Eating window countdown
  • Fasting phases visualization
  • Support for multiple fasting methods
  • Streak tracking with grace periods
  • Pattern insights
  • Weight and BMI tracking
  • Smart notifications
  • 100% offline functionality
Features
Read full description

Just Fast is the intermittent fasting timer that tracks both your fast and your eating window — a combination no other fasting app offers. Whether you're new to 16:8 or pushing into 20:4, OMAD, or custom schedules, Just Fast gives you a clear, distraction-free timer alongside the insights to understand what your body is doing and build habits that stick. EATING WINDOW COUNTDOWN — ONLY IN JUST FAST Most fasting apps tell you when your fast ends. Just Fast also tells you when your eating window closes. Know exactly how much time you have left to eat, so you stop overrunning your window by accident. KEY FEATURES • Eating Window Countdown — track when your eating window closes, not just when your fast ends • Fasting Phases — see fat burning, ketosis, and autophagy stages visualized in real time • All Major Fasting Methods — 16:8, 18:6, 20:4, OMAD, 14:10, 12:12, 24h, and custom durations • Streak Tracking with Grace Periods — maintain your momentum even on tough days • Pattern Insights — review your fasting history and discover your most consistent windows • Weight Tracking with BMI — log weight entries and track progress over time • Smart Notifications — reminders that support your schedule, not disrupt it • Beginner-Friendly Onboarding — choose your goal, fasting expertise, and preferred schedule in minutes • 100% Offline — no account, no signup, no cloud required • 15 Languages — English, German, French, Spanish, Polish, Portuguese, Italian, Japanese, Korean, Arabic, Russian, Swedish, Finnish, Norwegian, Turkish UNDERSTAND YOUR FAST, NOT JUST YOUR TIMER Just Fast visualizes the metabolic phases of fasting as they happen: fat burning begins around hour 12, ketosis deepens past hour 18, autophagy activates beyond hour 24. You do not need a biology degree — the app shows you where you are and what your body is doing. FREE AND LIGHTWEIGHT All core features are free. No subscription. No paywall. Just Fast is also one of the lightest full-featured fasting apps available — under 50MB download, compared to 200MB+ for most competitors. Fast to download, fast to start. Note: The app is free with light banner ads on secondary screens (history, settings). The main fasting timer screen is completely ad-free. PERFECT FOR • Beginners starting their first 16:8 protocol • Intermediate fasters exploring 18:6, 20:4, or OMAD • Anyone who wants fasting phases explained without complexity • People managing multiple fasting schedules across 15 languages • Privacy-conscious users who prefer no-account apps Download Just Fast and start your first fast today — no signup required. --- Privacy Policy: https://justfast.app/privacy Support: support@justfast.app

About

Simple Fasting

Features
Read full description

What you can do with Simple Fasting • Track active fasting sessions with a clear, easy-to-read timer • Plan upcoming fasting periods in advance • Review past fasting sessions and monitor your progress over time • Keep your fasting routine organized in one simple place Designed to stay simple Simple Fasting focuses on clarity and ease of use. No clutter, no distractions - just the features you need to support your fasting goals. Whether you’re new to fasting or already experienced, Simple Fasting helps you stay on track and build better habits over time.

Screenshots

Just Fast4 screens
Simple Fasting4 screens

Verdict

The call

The clearest difference is in-app purchases: Just Fast at none against Simple Fasting's 1. Just Fast also leads on update cadence (every 3 weeks vs every 4 months). On price, ads, 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. Simple Fasting sells 1 one-off in-app purchase. Just Fast asks for nothing beyond the download.

UpkeepUpdate frequency

Just Fast ships an update every 3 weeks, Simple Fasting every 4 months. The most recent releases landed on September 20, 2026 and September 26, 2026 respectively.

Scorecard2 real differences · 8 level
Just Fast versus Simple Fasting: the parameters behind the verdict, then further details
ParameterJust FastSimple Fasting
PriceFreeFree
Rating5.0 (7 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings7 — better—
Update frequencyEvery 3 weeks — betterEvery 4 months
AdsYesYes
In-app purchasesNo — betterYes
MonetizationAd-supported—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS14.0 — better15.0
Further details — not scored
Size47 MB28 MB
Age rating17+4+
DeveloperAdrian CabalaUIXLY AS

In-app purchases

None

Just Fast

No in-app purchases

1 purchases

Simple Fasting

One-time1
  • Remove ADs$0.99

Questions

Is Just Fast free?
Just Fast is free to download, with no in-app purchases.
Is Simple Fasting free?
Simple Fasting is free to download, with in-app purchases available.
Do Just Fast or Simple Fasting have ads?
Both Just Fast and Simple Fasting show ads.
Which is updated more often, Just Fast or Simple Fasting?
Just Fast ships an update every 3 weeks, and Simple Fasting every 4 months. Most recently, Just Fast was updated on September 20, 2026 and Simple Fasting on September 26, 2026.

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