Comparison

Flex AI Workout Trainer & Log vs BioFIT Intelligence

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

BioFIT Intelligence

Features
Read full description

Your body tells you when to push and when to back off. BioFIT reads that signal from Apple Health and builds your training around it. **No account. No ads. Nothing to set up but your goal.** ### TODAY Start your day with a recovery score based on sleep, heart-rate variability, and resting heart rate—with the reasoning behind the score, not just the number. Tap your score to see what raised it and what pulled it down. Steps, distance, and your streak are right alongside it. ### TRAINING Build a four-week training plan around your: • Goal • Experience level • Available equipment • Training days Your plan adapts to your recovery. If you've flagged a joint, BioFIT can swap movements that load it for alternatives designed to spare it. Track sets, rest, and timing as you train, with form guidance when you want it. Your plan isn't locked. Rebuild it whenever your goal changes. ### HEALTH LAB Keep important health measurements together in one place. • Log and classify blood pressure, with your entries saved back to Apple Health • View blood oxygen • Resting heart rate • Breathing disturbances • AFib history • Glucose BioFIT reads these measurements from Apple Health so you can see your health data alongside your training. ### PROGRESS Understand how your body and training change over time. • Recovery trends • Body composition • FFMI • Biometrics at a glance • Personal records • Completed sessions • Manual weigh-ins Your completed workouts and personal records build a picture of your progress as you train. ### A STEADY HABIT, NOT A STREAK YOU DREAD An optional 8:00 AM reminder lets you know your recovery score is ready. Take a look, then get on with your day. Miss a session? Nothing scolds you. BioFIT simply reads today's recovery and adjusts your training accordingly. Consistency is the point—not perfection. ### BIOFIT PRO Unlock additional tools with BioFIT Pro: • 30- and 90-day recovery trends • Weekly training review • Shareable Deep Scan report • Unlimited AI training plans • Strip and kit log for at-home test results ### AI, ONLY IF YOU WANT IT BioFIT can optionally use Google Gemini to generate your daily brief, weekly review, and personalized workout plans. When enabled, BioFIT sends summary figures from your health data—not your name, dates, or raw health records. If you leave AI turned off, BioFIT still works. Your health analysis remains available in the app, and workout plans can be built directly on your iPhone. ### YOUR DATA Your health data stays in Apple Health and on your device. BioFIT reads only the health information it needs for its features and writes only the blood pressure readings that you enter yourself. There are: • No accounts • No tracking • No advertising ### GETTING THE MOST FROM BIOFIT Recovery scoring uses overnight heart-rate variability and sleep data. Wearing an Apple Watch while you sleep provides the fullest recovery picture. Don't have an Apple Watch? You can still use training, Health Lab, body composition, progress tracking, and other core features. ### IMPORTANT BioFIT Intelligence is a fitness and wellbeing tool. It does not diagnose, treat, or prevent any medical condition and is not a substitute for advice from a qualified healthcare professional. ### SUBSCRIPTION BioFIT Pro is available as a monthly or annual auto-renewing subscription with a 7-day free trial. Payment is charged to your Apple Account at confirmation of purchase. Your subscription automatically renews unless cancelled at least 24 hours before the current subscription period ends. You can manage or cancel your subscription through your Apple Account settings. ### TERMS & PRIVACY Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://nasdin.com/BioFIT-Intelligence-app/privacy_policy.html

Screenshots

Flex AI Workout Trainer & Log4 screens
BioFIT Intelligence4 screens

Verdict

The call

The clearest difference is update cadence: BioFIT Intelligence at every 4 days against Flex AI Workout Trainer & Log's every 9 days. On price, ads, in-app purchases 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. Flex AI Workout Trainer & Log sells 8 in-app purchases, starting at $12.99 per month and BioFIT Intelligence sells 2 in-app purchases, starting at $9.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Flex AI Workout Trainer & Log ships an update every 9 days, BioFIT Intelligence every 4 days. The most recent releases landed on October 17, 2026 and October 13, 2026 respectively.

Scorecard1 real difference · 9 level
Flex AI Workout Trainer & Log versus BioFIT Intelligence: the parameters behind the verdict, then further details
ParameterFlex AI Workout Trainer & LogBioFIT Intelligence
PriceFreeFree
Rating4.6 (2.4K ratings) — better—
Positive reviews69.0% of reviews—
Number of ratings2.4K — better—
Update frequencyEvery 9 daysEvery 4 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationFreemium—
DevicesiPhone, Apple Watch — betteriPhone
Requires iOS18.0 — better18.2
Further details — not scored
Size574 MB17 MB
Age rating17+12+
DeveloperFlex Artificial Intelligence Inc.Nasir Uddin

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

BioFIT Intelligence

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

BioFIT Intelligence

Subscriptions2
  • BioFIT Pro monthly7 Days trial$9.991 Month
  • BioFIT Pro Annual7 Days trial$99.991 Year

Questions

Is Flex AI Workout Trainer & Log free?
Flex AI Workout Trainer & Log is free to download, with in-app purchases available.
Is BioFIT Intelligence free?
BioFIT Intelligence is free to download, with in-app purchases available.
Do Flex AI Workout Trainer & Log or BioFIT Intelligence have ads?
Neither Flex AI Workout Trainer & Log nor BioFIT Intelligence shows ads.
Which is updated more often, Flex AI Workout Trainer & Log or BioFIT Intelligence?
Flex AI Workout Trainer & Log ships an update every 9 days, and BioFIT Intelligence every 4 days. Most recently, Flex AI Workout Trainer & Log was updated on October 17, 2026 and BioFIT Intelligence on October 13, 2026.

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