Comparison

Flex AI Workout Trainer & Log vs Repay

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

Head to head
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.

About

Repay

Features
Read full description

Earn your screen time. Move first, scroll second. Repay is a screen time blocker that turns movement and focused learning into minutes you can spend. Choose the apps and websites that distract you, put them behind Apple Screen Time, then earn your way back in. HOW IT WORKS • Pick apps, categories or websites to shield. • Earn minutes with push-ups, squats, planks, quick math or a focused language lesson. • Bank your reward and open the vault when you are ready. • Your selected apps lock again when your earned time runs out. EFFORT THAT COUNTS Repay uses your iPhone's sensors to help count exercise: on-device camera movement detection for push-ups, camera pose detection for squats, and a flat-surface timer for planks. If a sensor is unavailable, rep-based workouts offer an honor-mode fallback. Prefer a non-exercise option? Solve increasingly challenging math problems for a smaller reward. LEARN LANGUAGES, EARN MINUTES Study Spanish and other languages through guided vocabulary, listening, translation and spaced review. Lessons work offline and only pay out after every question is correct. MAKE THE DEAL YOURS Set an exchange rate from 15 seconds to 10 minutes per rep. Stay under your daily vault spending limit to keep your streak, then review your seven-day chart and transaction history. BUILT FOR PRIVACY Your Screen Time choices are handled with Apple's privacy-preserving picker. Workout history and your time balance are stored on your device. Squat video is processed live on device and is never stored or uploaded. REPAY PRO The core loop is free: push-ups and math. Repay Pro adds squats, planks, language lessons and custom exchange rates. It is an optional auto-renewable subscription; choose monthly or annual access and pay through Apple. No account required. No ads. Just a fairer exchange between movement and scrolling. Privacy Policy: https://repayapp.info/privacy Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Flex AI Workout Trainer & Log4 screens
Repay4 screens

Verdict

The call

Flex AI Workout Trainer & Log and Repay are too close to call on the numbers: across 5 compared parameters — price, ads, in-app purchases and device support among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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. Flex AI Workout Trainer & Log sells 8 in-app purchases, starting at $12.99 per month and Repay sells 2 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

ScorecardNo meaningful differences
Flex AI Workout Trainer & Log versus Repay: the parameters behind the verdict, then further details
ParameterFlex AI Workout Trainer & LogRepay
PriceFreeFree
Rating4.6 (2.4K ratings) — better—
Positive reviews69.0% of reviews—
Number of ratings2.4K — better—
Update frequencyEvery 9 days—
AdsNoNo
In-app purchasesYesYes
MonetizationFreemium—
DevicesiPhone, Apple Watch — betteriPhone
Requires iOS18.017.0 — better
Further details — not scored
Size574 MB24 MB
Age rating17+4+
DeveloperFlex Artificial Intelligence Inc.Jasper Van Rooijen

Bugs and requests

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

Repay

Not enough reviews yet to summarise bugs or requests.

In-app purchases

8 purchases

Flex AI Workout Trainer & Log

Subscriptions6
  • Premium Subscription Monthly$12.991 Month
  • Premium Plus Monthly$29.991 Month
  • Premium Plus Family Monthly$69.991 Month
Show 3 more
  • Premium Yearly Subscription$79.991 Year
  • Premium Plus Yearly7 Days trial$191.991 Year
  • Premium Plus Family Yearly7 Days trial$499.991 Year
One-time2
  • 1 Month Free PremiumFree
  • Lifetime Free PremiumFree
2 purchases

Repay

Subscriptions2
  • Repay Pro Monthly$0.991 Month
  • Repay Pro Annual$6.991 Year

Questions

Is Flex AI Workout Trainer & Log free?
Flex AI Workout Trainer & Log is free to download, with in-app purchases available.
Is Repay free?
Repay is free to download, with in-app purchases available.
Do Flex AI Workout Trainer & Log or Repay have ads?
Neither Flex AI Workout Trainer & Log nor Repay shows ads.

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