Comparison

Kaizer vs Bustafit

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

Head to head
About

Kaizer

This AI-powered fitness planner creates hyper-personalized workout routines based on your goals, limitations, and available equipment. It intelligently adapts your training over time to ensure continuous progress and prevent burnout.

Highlights
  • AI-powered routine creation via natural language
  • Hyper-personalized plans based on user data
  • Smart progressive overload and weight updates
  • Exercise replacement suggestions
  • Professional coaching principles integrated
Features
Read full description

Kaizer is the app where you train with your trainer or your gym: your routine, your classes, the chat and your progress, all in one place. WITH YOUR GYM If your gym runs on Kaizer, you join with the link they share and see the app with their name, logo and color. Book your classes or keep a fixed spot, read your gym's news and train with the routine they assign you. WITH YOUR TRAINER Your trainer sends you your routines, follows your progress, adjusts whatever needs adjusting, chats with you and asks for form videos. All of it in one place, without leaning on three other apps. NO TRAINER YET? Browse the marketplace inside the app. Every profile shows how that coach works, their specialties and whether they train online, in person or both. Subscribe to the one that fits and they are notified the moment you join. YOUR SESSIONS, IN DETAIL Sets, reps, load, rest. Supersets, circuits and dropsets when your plan calls for them. Every exercise ships with an illustration of the muscle it works, so you know what you are aiming at before you lift. ASSISTED PROGRESSION Week over week, Kaizer writes the loads of your upcoming sessions from what you actually lifted. You always know what to do when you walk into the gym, and the weight on the bar keeps moving. SMART REPLACE Machine taken? A movement you cannot do today? Kaizer suggests alternatives that keep the point of the exercise intact, so swapping one leaves the rest of the plan standing. EVERYTHING IN ONE PLACE - Direct chat with your trainer: text, photos, files and voice notes - Nutrition plan with meals, recipes and macros, when your trainer sends one - Full training history, streaks and progress your trainer sees too - 1,500+ exercises with illustrations - Apple Health sync and Live Activities while you train - Rest timer that runs on your lock screen TRAINING ON YOUR OWN? You can also use Kaizer without a trainer. Describe what you want in plain language (four days a week, bad knees, dumbbells only) and Kaizer builds a complete structured program in seconds, and keeps adapting it as you log your work. Kaizer works in Spanish, English and Portuguese, in 20+ countries. Terms of Service: https://kaizer.app/en/terms-and-conditions Privacy Policy: https://kaizer.app/en/privacy-policy

About

Bustafit

This app helps you maximize hypertrophy training by logging weights, reps, and RIR. It provides practical load and rep recommendations for progressive overload and connects you with your online coach for personalized guidance.

Highlights
  • Log weights, reps, and RIR
  • Get load and rep recommendations
  • Connect with online coach
  • Follow structured routines
  • AI-assisted video technique review
  • Track rest with timers
  • Log nutrition and macros
Features
Read full description

Bustafit is built to help you maximize your hypertrophy training, from beginner to elite. It combines a weight and workout log, structured routines, and a connection to your own online coach so you know what to do today and how to progress. The app remembers your last useful set and turns weights, reps and RIR into practical load and rep recommendations. Use that guidance for progressive overload, plateau decisions, and a clearer next exposure without scattered notes. If you already work with a trainer, connect them by code or link. With your permission, they can review your profile and history, assign training blocks, leave directives, adjust saved plans, and view your technique reviews. What you can do with Bustafit: - Log weights, loads, reps and RIR for every set. - See your last useful reference before training. - Get load and rep recommendations based on performance. - Follow structured routines for the gym, home or dumbbell-only training. - Adapt training to experience levels from beginner to elite. - Use alternatives when equipment is busy or pain appears. - Review weekly volume, history and workout continuity. - Track rest with timers and alerts. - Use AI-assisted video technique review and keep results in your history. - Keep nutrition, calories and macros alongside training. - Follow supplement reminders saved by you or your coach. - Train connected to your own online coach. Bustafit brings tracking, progression, technique, nutrition and coaching together to help you make a clearer decision for every set. The app is not medical advice and does not diagnose, treat, cure or prevent any disease. Nutrition guidance is informational; supplement reminders do not prescribe or validate doses. Ask a qualified health professional or registered dietitian when appropriate.

Screenshots

Kaizer4 screens
Bustafit4 screens

Verdict

The call

The clearest difference is in-app purchases: Bustafit at none against Kaizer's 11. Kaizer's advantage is ratings volume (9 vs 2). On price, rating, review sentiment and update cadence 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. Kaizer sells 11 in-app purchases, starting at $3.99 per 7 days. Bustafit asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for Kaizer against 5.0 for Bustafit. Both are backed by a comparable volume of ratings — 9 and 2 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

Kaizer ships an update every 8 days, Bustafit fortnightly. The most recent releases landed on October 24, 2026 and October 10, 2026 respectively.

Scorecard3 real differences · 7 level
Kaizer versus Bustafit: the parameters behind the verdict, then further details
ParameterKaizerBustafit
PriceFreeFree
Rating5.0 (9 ratings)5.0 (2 ratings)
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings9 — better2
Update frequencyEvery 8 days — betterFortnightly
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemiumFree — better
DevicesiPhone, iPadiPhone, iPod
Requires iOS16.415.0 — better
Further details — not scored
Size109 MB17 MB
Age rating4+4+
DeveloperKAIZERMonica Andrea Luna Pinilla

Customer experience

Kaizer

All ratings9 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bustafit

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

11 purchases

Kaizer

Subscriptions10
  • Pro Weekly3 Days trial$3.997 Days
  • Pro Monthly3 Days trial$8.991 Month
  • Trainer Plan — $39.99$39.991 Month
Show 7 more
  • Pro Yearly7 Days trial$39.991 Year
  • Trainer Plan — $59.99$59.991 Month
  • Trainer Plan — $79.99$79.991 Month
  • Trainer Plan — $99.99$99.991 Month
  • Trainer Plan — $109.99$109.991 Month
  • Trainer Plan — $129.99$129.991 Month
  • Trainer Plan — $159.99$159.991 Month
One-time1
  • Pro Lifetime$89.99
None

Bustafit

No in-app purchases

Questions

Is Kaizer free?
Kaizer is free to download, with in-app purchases available.
Is Bustafit free?
Bustafit is free to download, with no in-app purchases.
Which has better reviews, Kaizer or Bustafit?
Kaizer and Bustafit are both rated 5.0 out of 5 on the App Store, from 9 and 2 ratings respectively.
Do Kaizer or Bustafit have ads?
Neither Kaizer nor Bustafit shows ads.
Which is updated more often, Kaizer or Bustafit?
Kaizer ships an update every 8 days, and Bustafit fortnightly. Most recently, Kaizer was updated on October 24, 2026 and Bustafit on October 10, 2026.

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