Comparison

Fast vs Ai1

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

Head to head
About

Fast

This app helps you track intermittent fasting routines, monitor progress, and analyze health data. It offers educational content, motivational challenges, and a journal to record your feelings. Connect with friends for support and motivation on your wellness journey.

Highlights
  • Fasting timer and tracker
  • Progress analytics and history
  • Educational 'Know It' section
  • Motivational challenges and trophies
  • Mood tracker and journal
  • Health app integration (steps)
  • Fasting buddy feature
Features
Read full description

Fast: Fasting Tracker & Timer helps you build consistent fasting habits with flexible fasting plans, body weight logging, water intake tracking, reminders, and detailed progress insights. Whether you're new to intermittent fasting or already following a routine, the app provides the tools to stay organized and work toward your personal health and wellness goals. Choose a fasting plan, customize your schedule, and track every fast in one place with an easy-to-use fasting tracker. FASTING PLANS Find a fasting schedule that works for your lifestyle. Choose from 12:12, 13:11, 14:10, 15:9, 16:8, 17:7, 18:6, 19:5, 20:4, 21:3, 22:2, 23:1, MWF, TTS, or create your own custom fasting plan. Whether you're starting intermittent fasting or maintaining an existing routine, you can choose a plan that suits your goals. FASTING TRACKER & TIMER Track active and completed fasts with an intuitive fasting tracker and timer. Review your fasting history and monitor your consistency over time. BODY WEIGHT & WATER TRACKING Log your body weight and monitor changes throughout your fasting routine. Track your daily water intake to stay hydrated and build healthier habits alongside your fasting schedule. SMART REMINDERS Stay on schedule with fasting reminders and water intake reminders. Customize notifications to help you start and end your fasting window on time while maintaining your daily hydration routine. ANALYTICS & HISTORY Review your fasting sessions, body weight, hydration logs, activity, and history with easy-to-understand analytics that help you monitor your progress and stay consistent. INFORMATIVE BLOGS Learn more about intermittent fasting through informative blogs covering healthy habits, wellness topics, and practical guidance to help you better understand your fasting routine. FASTING BUDDIES Stay motivated by fasting together. Invite friends, track each other's progress, and encourage one another throughout your fasting journey with the Buddy feature. ACTIVITY SUPPORT Sync your activity data to keep your fasting progress and daily activity organized in one place for a more complete overview of your routine. Whether you're following a 16:8 fasting schedule, exploring different intermittent fasting plans, or creating a custom fasting routine, Fast: Fasting Tracker & Timer gives you the tools to stay organized and build lasting healthy habits. DISCLAIMER This app is intended for informational and lifestyle purposes only and does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before starting any fasting routine, especially if you have an existing medical condition, are pregnant, or have specific dietary requirements. PRIVACY POLICY https://maximaapps.com/fasting/privacy_policy.html TERMS OF USE https://maximaapps.com/fasting/terms-of-use.html GET IN TOUCH Have questions, feedback, or suggestions? We'd love to hear from you. Contact us through the app or email us at feedback@maximaapps.com.

About

Ai1

This app simplifies intermittent fasting with an easy-to-understand interface. It supports users in their journey towards weight loss, improved concentration, and overall well-being, regardless of their experience level.

Highlights
  • Easy intermittent fasting tracking
  • Simple interface
  • Supports weight loss goals
  • Improves concentration
  • Enhances overall well-being
  • Suitable for beginners and experts
Features
Read full description

** Ayuno intermitente fácil y sencillo** Ai1 es una aplicación pensada en las necesidades básicas de la gente que practica el ayuno intermitente, sin complejidades, fácil de entender y con una interfaz sencilla. Ya sea que tu ayuno intermitente lo hagas para bajar de peso, mejorar concentración, incrementar tu estado salud o ánimo en general, esta APP será la compañera perfecta en tu camino desde principiante hasta experto. Consulta nuestro aviso de privacidad en https://soysei.com/privacidad Consulta nuestros términos y condiciones de uso en https://soysei.com/terminos

Screenshots

Fast4 screens
Ai14 screens

Verdict

The call

The clearest difference is rating: Fast at 4.7 against Ai1's 2.8. Fast also leads on ratings volume (3.3K vs 4). Ai1's advantage is in-app purchases (none vs 8) and update cadence (monthly vs every 2 months). 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. Fast sells 8 in-app purchases, starting at $4.99 per month. Ai1 asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Fast holds the better App Store score, 4.7 against 2.8. That said, the two scores are not equally well evidenced: Fast has 3.3K ratings behind it against 4, so its average is the more settled of the two.

UpkeepUpdate frequency

Fast ships an update every 2 months, Ai1 monthly. The most recent releases landed on October 29, 2026 and October 8, 2026 respectively.

Scorecard6 real differences · 4 level
Fast versus Ai1: the parameters behind the verdict, then further details
ParameterFastAi1
PriceFreeFree
Rating4.7 (3.3K ratings) — better2.8 (4 ratings)
Positive reviews74.6% of reviews—
Number of ratings3.3K — better4
Update frequencyEvery 2 monthsMonthly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, Apple Watch — betteriPhone, iPod
Requires iOS18.611.0 — better
Further details — not scored
Size116 MB38 MB
Age rating12+4+
DeveloperMaxima AppsSiempre Somos S de RL de CV

Customer experience

Fast

All ratings3,300 ratings
Positive91.8%
Neutral4.8%
Negative3.5%
Written reviews189 reviews
Positive74.6%
Neutral10.6%
Negative14.8%

Ai1

All ratings4 ratings
Positive25.0%
Neutral0.0%
Negative75.0%

Bugs and requests

Fast

Reported bugs

3 issues
  • Timer not accurately recording fasting times
  • Inability to update weight in app
  • Crashing when trying to view friend's status

Requested features

4 requests
  • Option to edit fasting start/end times
  • More detailed analytics and progress tracking
  • Improved syncing and data saving reliability
  • Expanded customization options

Ai1

Not enough reviews yet to summarise bugs or requests.

In-app purchases

8 purchases

Fast

Subscriptions6
  • Fast Premium Monthly$4.991 Month
  • Fasting Monthly$14.991 Month
  • Fasting Annually$19.991 Year
Show 3 more
  • Fasting Premium$27.993 Months
  • Fast Premium Yearly$29.991 Year
  • Fasting Premium Yearly$39.991 Year
One-time2
  • Fasting One Time Special Offer$19.99
  • Fasting Pro$49.99
None

Ai1

No in-app purchases

Questions

Is Fast free?
Fast is free to download, with in-app purchases available.
Is Ai1 free?
Ai1 is free to download, with no in-app purchases.
Which has better reviews, Fast or Ai1?
Fast is rated higher. Fast averages 4.7 out of 5 from 3.3K ratings, while Ai1 averages 2.8 from 4 ratings.
Do Fast or Ai1 have ads?
Neither Fast nor Ai1 shows ads.
Which is updated more often, Fast or Ai1?
Fast ships an update every 2 months, and Ai1 monthly. Most recently, Fast was updated on October 29, 2026 and Ai1 on October 8, 2026.

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