Comparison

Strong Workout Tracker Gym Log vs Flex AI Workout Trainer & Log

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

Head to head
About

Strong Workout Tracker Gym Log

This app helps you track your workouts and progress with an intuitive interface. It offers a wide range of exercises, detailed instructions, and advanced statistics to help you achieve your fitness goals. Easily log your routines, monitor personal records, and stay motivated on your fitness journey.

Highlights
  • Intuitive workout logging
  • Comprehensive exercise library
  • Apple Watch integration
  • Advanced progress statistics
  • Customizable routines
  • Cloud data backup
Features
Read full description

The most intuitive workout and exercise tracker for any fitness routine. Strong is the simplest and most intuitive workout tracker, designed to help you get better results from your workouts. Whether you want to gain strength or just stay healthy, join over 1.2 million people who have downloaded Strong to stay on track in the gym. “I’d suggest downloading the “Strong” app before you return to the gym. It’s that good” - CNBC “with apps like Strong, working out feels more like a game” - The Verge “I have used nearly every logging app since the App Store launched. This is the best bar none” “I use this every time I go to the gym and seriously couldn't train without it” “Simple. Intuitive. Functional. Exactly what I was looking for.” “This is bare bones and serious. Right on, and works perfectly... I wish I could give 10 stars.” “It's by far the most intuitive and easy to use workout app I’ve used.” Whether you’re a beginner or an experienced powerlifter, Strong provides everything you need to record your workouts as effortlessly and as quickly as possible. Unlike other fitness apps, Strong doesn’t bog you down with distractions and unnecessary gimmicks you’d never use. Strong is optimized for a progressive barbell routine such as Starting Strength or StrongLifts 5x5, but it is easily adaptable to any other routine of your choosing! FEATURES: • The simplest interface of any fitness app in the App Store • A comprehensive range of cardio and strength exercises - and add your own too! • Fully-featured Apple Watch app to log workouts with or without your iPhone • Add your own routines and easily choose between them • Detailed exercise instructions with a growing library of animated videos • Advanced Statistics show your personal records and progression and even calculate your one rep max and total weight lifted! • Built in Auto Countdown Timer to help record rest breaks • Support for multiple Exercise Types, including Assisted Bodyweight and Duration Exercises • Tag sets as Warm Up, Failure or Drop Sets • Supersets/Grouped Exercises • Track your progress with graphs for Volume and 1RM Progression • Automatically back up your data with Cloud Sync! • Built in body measurements tracker to record your weight and other vitals, with support for Apple Health • Warm Up Calculator tells you which weights to warm up with • Plate Calculator for when the weights get high • Support for Imperial (lbs) and Metric (kg) weights, or a combination of both • Add notes and progress pictures to your workouts • Share sheet makes sharing routines and workouts with friends easier than ever! • Export all of your data to Notes or Email in CSV format The free version of Strong can save unlimited workouts, but is limited to 3 custom routines. Upgrade to a Strong PRO subscription ($4.99/month or $29.99/year) for an unlimited number of routines and to unlock additional PRO features. Strong will automatically charge your iTunes Account at the end of your subscription or free trial period unless auto-renew is turned off at least 24 hours before the end of your current period. Subscriptions renew at the original price. You can turn off auto-renew at any time and still receive full functionality until the end of your current period, but no refund can be provided for unused portions of the subscription. Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable. If you’ve previously purchased “Unlock Strong” or “Strong Combo Pack”, you’ll be able to use the Restore Purchases option in the app for access to all Strong PRO features. These prices are for customers in the United States and may vary depending on your iTunes Account settings. In-app purchases and subscriptions cannot be shared using Family Sharing. Strong Terms of Service - https://help.strongapp.io/article/179-strong-terms-of-service Strong Privacy Policy - https://www.iubenda.com/privacy-policy/7760215

About

Flex AI Workout Trainer & Log

This app uses AI to provide personalized workout plans and real-time form feedback for weightlifters. It tracks progress, offers adaptive progression, and includes motivational features like leaderboards and streaks. It's designed for all experience levels, from beginners to pros.

Highlights
  • AI personal trainer
  • Real-time form feedback
  • Personalized workout plans
  • Adaptive progression
  • Strength tracking
  • Community leaderboards
  • Apple Watch integration
Features
Read full description

Flex AI is the world’s first true AI personal trainer — built for lifters who want to train smarter, progress faster, and perfect their form. Whether you’re chasing size, strength, or consistency, Flex uses real-time AI to guide every rep, adjust your program, and keep you motivated through challenges, leaderboards, and streaks. - Your AI Coach, Every Rep Personalized workouts built automatically by AI personas that learn your goals, history, and preferences. Real-time form feedback powered by patented computer-vision AI — get instant corrections on squats, bench, deadlift, rows, and more. Adaptive progression and deloading backed by sports-science principles — no spreadsheets, no guesswork. - Train Smarter — See Results AI tracks your strength curve and increases weight when you’re ready. Visual progress graphs show PRs, volume, and recovery trends. Track sets, reps, and tempo with a tap — or automatically with Apple Watch. - Stay Motivated & Connected Join a global community of lifters. Compete on leaderboards, build streaks, and earn badges. Post progress photos, celebrate milestones, and share results. - Accessible to Everyone Free to start with all core features included. Upgrade anytime for advanced AI coaching and premium analytics. Designed for all experience levels — from beginners to pros. - Why Flex AI Real-time AI form feedback (patented) Adaptive, science-based programming Progress tracking & recovery insights Gamified streaks + leaderboards Apple Watch integration Built for hypertrophy & strength goals Start Training Smarter — Today Download Flex AI and experience personal training powered by real AI. Perfect your form. Unlock your best lift. Train smarter — free on iPhone + Apple Watch.

Screenshots

Strong Workout Tracker Gym Log4 screens
Flex AI Workout Trainer & Log4 screens

Verdict

The call

The clearest difference is rating: Strong Workout Tracker Gym Log at 4.9 against Flex AI Workout Trainer & Log's 4.6. Strong Workout Tracker Gym Log also leads on ratings volume (108K vs 2.4K) and chart position (#62 vs unranked). On price, review sentiment, update cadence and ads 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. Strong Workout Tracker Gym Log sells 11 in-app purchases, starting at $3.99 per month and Flex AI Workout Trainer & Log sells 8 in-app purchases, starting at $1.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Strong Workout Tracker Gym Log holds the better App Store score, 4.9 against 4.6. That said, the two scores are not equally well evidenced: Strong Workout Tracker Gym Log has 108K ratings behind it against 2.4K, so its average is the more settled of the two. Written reviews complicate that: 65% of Strong Workout Tracker Gym Log's written reviews are positive against 69% of Flex AI Workout Trainer & Log's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Strong Workout Tracker Gym Log ships an update every 2 weeks, Flex AI Workout Trainer & Log every 9 days. The most recent releases landed on September 25, 2026 and September 23, 2026 respectively.

Scorecard4 real differences · 7 level
Strong Workout Tracker Gym Log versus Flex AI Workout Trainer & Log: the parameters behind the verdict, then further details
ParameterStrong Workout Tracker Gym LogFlex AI Workout Trainer & Log
PriceFreeFree
Rating4.9 (108K ratings) — better4.6 (2.4K ratings)
Positive reviews65.2% of reviews69.3% of reviews — better
Number of ratings108K — better2.4K
Update frequencyEvery 2 weeksEvery 9 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFreemiumFreemium
Best chart rank#62 — better—
DevicesiPhone, iPod, Apple Watch — betteriPhone, Apple Watch
Requires iOS15.0 — better18.0
Further details — not scored
Size129 MB574 MB
Age rating4+17+
DeveloperStrong Fitness PTE LimitedFlex Artificial Intelligence Inc.

Customer experience

Strong Workout Tracker Gym Log

All ratings108,483 ratings
Positive97.8%
Neutral1.0%
Negative1.3%
Written reviews1,298 reviews
Positive65.2%
Neutral10.5%
Negative24.3%

Flex AI Workout Trainer & Log

All ratings2,405 ratings
Positive92.0%
Neutral2.6%
Negative5.4%
Written reviews303 reviews
Positive69.3%
Neutral6.6%
Negative24.1%

User reviews

Strong Workout Tracker Gym Log

From 108K App Store ratings

What we love

  • 🚀 Excellent workout tracking
  • 👍 Clean, intuitive interface
  • 📊 Comprehensive data and progress tracking
  • ⌚ Seamless Apple Watch integration
  • 🔍 Extensive exercise library

Room to improve

  • 🔋 High battery consumption
  • 🔒 Concerns about subscription model and pricing
  • 🐛 Apple Watch app issues and syncing problems
  • 🔧 Difficulty editing or deleting exercises/routines

Flex AI Workout Trainer & Log

From 2.4K App Store ratings

What we love

  • 🚀 Detailed workout tracking
  • 👍 Customizable workouts
  • 🔒 Comprehensive exercise library
  • 💡 Helpful progress tracking
  • 👍 Clean and intuitive interface

Room to improve

  • 🐛 Glitches and bugs
  • 💰 Expensive premium subscription
  • 🔒 Limited functionality without premium
  • 🐛 Inconsistent rest timer
  • 🐛 Workout data loss

Bugs and requests

Strong Workout Tracker Gym Log

Reported bugs

3 issues
  • Workouts not syncing properly between devices
  • Exercises disappearing from saved routines
  • Crashes and stability issues, especially on Apple Watch

Requested features

5 requests
  • Add ability to track body part volume and focus
  • Improve exercise search and categorization
  • Implement more advanced analytics and reporting
  • Allow pausing of workouts on Apple Watch
  • Add support for more workout types (e.g. cardio)

Flex AI Workout Trainer & Log

Reported bugs

3 issues
  • App crashes on iOS 16 update
  • Inability to log workouts on previous days
  • Inconsistent syncing between app and Apple Watch

Requested features

4 requests
  • Offline workout mode
  • Ability to save and reuse custom workout plans
  • Muscle group targeting and analytics
  • Social features and community integration

In-app purchases

11 purchases

Strong Workout Tracker Gym Log

Subscriptions6
  • Strong PRO1 Month trial$3.991 Month
  • Strong PRO (1 Month)1 Month trial2 variants$4.991 Month
  • Strong PRO (6 Months)1 Month trial$19.996 Months
Show 3 more
  • Strong PRO (1 Year)$23.991 Year
  • Strong PRO (1 Year)$29.991 Year
  • Strong PRO (1 Year)2 Months trial$29.991 Year
One-time5
  • Power Pack (Legacy)$3.99
  • Unlock Strong (Legacy)$4.99
  • Unlock + Power Pack (Legacy)$6.99
Show 2 more
  • Strong PRO Forever$79.99
  • Strong PRO Forever$99.99
8 purchases

Flex AI Workout Trainer & Log

Subscriptions6
  • Premium Subscription Monthly$1.991 Month
  • Premium Plus Monthly$2.991 Month
  • Premium Yearly Subscription$9.991 Year
Show 3 more
  • Premium Plus Family Monthly$9.991 Month
  • Premium Plus Yearly7 Days trial$19.991 Year
  • Premium Plus Family Yearly7 Days trial$49.991 Year
One-time2
  • 1 Month Free PremiumFree
  • Lifetime Free PremiumFree

Questions

Is Strong Workout Tracker Gym Log free?
Strong Workout Tracker Gym Log is free to download, with in-app purchases available.
Is Flex AI Workout Trainer & Log free?
Flex AI Workout Trainer & Log is free to download, with in-app purchases available.
Which has better reviews, Strong Workout Tracker Gym Log or Flex AI Workout Trainer & Log?
Strong Workout Tracker Gym Log is rated higher. Strong Workout Tracker Gym Log averages 4.9 out of 5 from 108K ratings, while Flex AI Workout Trainer & Log averages 4.6 from 2.4K ratings.
Do Strong Workout Tracker Gym Log or Flex AI Workout Trainer & Log have ads?
Neither Strong Workout Tracker Gym Log nor Flex AI Workout Trainer & Log shows ads.
Which is updated more often, Strong Workout Tracker Gym Log or Flex AI Workout Trainer & Log?
Strong Workout Tracker Gym Log ships an update every 2 weeks, and Flex AI Workout Trainer & Log every 9 days. Most recently, Strong Workout Tracker Gym Log was updated on September 25, 2026 and Flex AI Workout Trainer & Log on September 23, 2026.

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