Comparison

CodonRX vs Fastology

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

Head to head
About

CodonRX

This app helps users understand their digestive health by tracking symptoms, mood, and intake. It provides dosage reminders for a specific probiotic and visualizes progress over time. Designed as a companion to a scientifically advanced probiotic, it aims to empower users in managing their gut wellness.

Highlights
  • Symptom, mood, and intake logging
  • Probiotic dosage reminders
  • Progress visualization
  • Daily tracking
  • Insightful feedback on body response
Features
Read full description

Tired of guessing what's causing your digestive discomfort? Take control of your gut health journey with the CodonRX Companion App, your free, all-in-one tool for understanding your body and tracking your progress. Designed exclusively for users of CodonRX probiotics, this app is your partner in achieving digestive wellness. Track What Matters, Effortlessly: - Dynamic Daily Tracker: Log your symptoms, bowel movements, daily intake, and mood in seconds. Our intuitive interface makes it easy to stay consistent. - Dosage Reminders: Never miss a dose with in-app reminders for your CodonRX. - See Your Progress: Our powerful tracking tools help you visualize your symptomatic trends over week and month long periods, providing insightful feedback on how your body is responding. Powered by Science, Designed for You: The CodonRX app is the companion to our scientifically advanced probiotic, CodonRX® | AI. Our flagship product is designed to reduce gut inflammation in patients suffering from IBS and IBD and promote overall gut wellness. - Proprietary, Patented Strain: Formulated with our exclusive strain of Lactobacillus acidophilus, NCK2025, developed at a leading US university. - Maximum Efficacy: Our acid-resistant, slow-release capsules ensure live probiotics are delivered directly to your bowel for maximum impact. Your Journey to a Healthier Gut Starts Now: At CodonRX, we believe in empowering you with cutting- edge science that is both accessible and easy to use. This app is the next step in our commitment to helping you manage your digestive health with confidence. Download the free CodonRX Companion App today and start tracking your way to a better you. Visit https://codonrx.com to learn more about the science behind CodonRX.

About

Fastology

This app provides structured tracking for intermittent fasting, going beyond simple timers. It helps users follow specific fasting schedules with clear phase progress, build consistency through streaks, and manage a flexible weekly plan. Focuses on discipline and reducing guesswork for a clearer fasting experience.

Highlights
  • Track various fast types (16:8, OMAD, extended)
  • Live phase-by-phase progress tracking
  • Build streaks from completed fasts
  • Flexible weekly fasting schedule
  • Review fasting history
  • Ask fasting questions with reviewed answers
  • Siri and Shortcuts integration
Features
Read full description

Fastology is a fasting tracker for people who want more than a timer. Fasting works when it is structured. Fastology helps you track 16:8, 18:6, OMAD, and extended fasts with clear phase progress, streaks that reflect completed fasts, and a weekly schedule that fits real life. Most fasting apps count hours. Fastology helps you follow through. WHY FASTOLOGY Structured, not reactive Follow a clear fasting rhythm instead of making it up as you go. See where you are Track each phase of the fast with live progress, so you always know where you stand and what comes next. Consistency over intensity Build streaks from completed fasts and focus on repeatability, not random extremes. Flexible weekly schedule Set your fasting rhythm for the week, then adjust specific days when life changes. Clear, focused experience No clutter. No noise. Just the tools that matter when you want to fast with more discipline and less guesswork. WHAT YOU CAN DO • Track 16:8, 18:6, OMAD, and extended fasts • Follow live phase-by-phase progress • Build streaks from completed fasts • Set a weekly schedule and adjust specific days • Review your fasting history over time • Ask fasting questions with reviewed answers and linked sources • Start a fast, check your phase, or search Fastology from Siri, Spotlight, Shortcuts, and Ask • On supported devices, use Apple Intelligence to explore your fasting history Fastology is built for people who want to fast with more clarity, more structure, and more follow-through.

Screenshots

CodonRX4 screens
Fastology4 screens

Verdict

The call

The clearest difference is iOS requirement: CodonRX at 15.1 against Fastology's 17.0. On price, rating, ratings volume and update cadence 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for CodonRX against 4.9 for Fastology. Both are backed by a comparable volume of ratings — 4 and 10 respectively.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 weeks. The most recent releases landed on September 27, 2026 and September 26, 2026 respectively.

Scorecard1 real difference · 9 level
CodonRX versus Fastology: the parameters behind the verdict, then further details
ParameterCodonRXFastology
PriceFreeFree
Rating5.0 (4 ratings) — better4.9 (10 ratings)
Positive reviews—100.0% of reviews
Number of ratings410 — better
Update frequencyEvery 3 weeksEvery 3 weeks
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPad, iPod — betteriPhone, Apple Watch
Requires iOS15.1 — better17.0
Further details — not scored
Size43 MB40 MB
Age rating4+4+
DeveloperProvaxusSmallScale Works LLC

Customer experience

CodonRX

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Fastology

All ratings10 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

CodonRX

No in-app purchases

None

Fastology

No in-app purchases

Questions

Is CodonRX free?
CodonRX is free to download, with no in-app purchases.
Is Fastology free?
Fastology is free to download, with no in-app purchases.
Which has better reviews, CodonRX or Fastology?
CodonRX is rated higher. CodonRX averages 5.0 out of 5 from 4 ratings, while Fastology averages 4.9 from 10 ratings.
Do CodonRX or Fastology have ads?
Neither CodonRX nor Fastology shows ads.
Which is updated more often, CodonRX or Fastology?
CodonRX ships an update every 3 weeks, and Fastology every 3 weeks. Most recently, CodonRX was updated on September 27, 2026 and Fastology on September 26, 2026.

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