Flex AI Workout Trainer & Log vs Milestone Strength
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- AI personal trainer
- Real-time form feedback
- Personalized workout plans
- Adaptive progression
- Strength tracking
- Community leaderboards
- Apple Watch integration
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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.
Milestone Strength
Achieve your health and fitness goals with a personalized plan. This application provides a structured approach to help you reach your objectives.
- Personalized fitness plans
- Goal achievement tracking
- Health and fitness focus
- Structured approach
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Download the Milestone Strength app. This app will let you see your plan designed to help you achieve your health and fitness goals.
Screenshots
Verdict
The clearest difference is rating: Flex AI Workout Trainer & Log at 4.6 against Milestone Strength's 4.1. Flex AI Workout Trainer & Log also leads on update cadence (every 9 days vs every 28 months) and ratings volume (2.4K vs 15). Milestone Strength's advantage is iOS requirement (12.4 vs 18.0). On price, review sentiment, ads and in-app purchases 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
Both are free to download. Flex AI Workout Trainer & Log sells 8 in-app purchases, starting at $1.99 per month and Milestone Strength sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.
Flex AI Workout Trainer & Log holds the better App Store score, 4.6 against 4.1. That said, the two scores are not equally well evidenced: Flex AI Workout Trainer & Log has 2.4K ratings behind it against 15, so its average is the more settled of the two. Written reviews complicate that: 69% of Flex AI Workout Trainer & Log's written reviews are positive against 75% of Milestone Strength's, so the app with the better star average is not the one people write more warmly about.
Flex AI Workout Trainer & Log ships an update every 9 days, Milestone Strength every 28 months. The most recent releases landed on September 29, 2026 and June 4, 2026 respectively.
| Parameter | Flex AI Workout Trainer & Log | Milestone Strength |
|---|---|---|
| Price | Free | Free |
| Rating | 4.6 (2.4K ratings) — better | 4.1 (15 ratings) |
| Positive reviews | 69.3% of reviews | 75.0% of reviews — better |
| Number of ratings | 2.4K — better | 15 |
| Update frequency | Every 9 days — better | Every 28 months |
| Ads | No | No |
| In-app purchases | Yes | Yes |
| Monetization | Freemium | Free with in-app purchases |
| Devices | iPhone, Apple Watch | iPhone, iPod |
| Requires iOS | 18.0 | 12.4 — better |
| Further details — not scored | ||
| Size | 574 MB | 14 MB |
| Age rating | 17+ | 4+ |
| Developer | Flex Artificial Intelligence Inc. | Layne Fletcher |
Customer experience
Flex AI Workout Trainer & Log
Milestone Strength
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
Milestone Strength
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Flex AI Workout Trainer & Log
- Premium Subscription Monthly$1.991 Month
- Premium Plus Monthly$2.991 Month
- Premium Yearly Subscription$9.991 Year
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- Premium Plus Family Monthly$9.991 Month
- Premium Plus Yearly7 Days trial$19.991 Year
- Premium Plus Family Yearly7 Days trial$49.991 Year
- 1 Month Free PremiumFree
- Lifetime Free PremiumFree
Milestone Strength
- Custom Training and Nutrition$449.99
Questions
Is Flex AI Workout Trainer & Log free?
Is Milestone Strength free?
Which has better reviews, Flex AI Workout Trainer & Log or Milestone Strength?
Do Flex AI Workout Trainer & Log or Milestone Strength have ads?
Which is updated more often, Flex AI Workout Trainer & Log or Milestone Strength?
Other comparisons
