Comparison

Trena vs Kaizer

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

Head to head
About

Trena

This app generates personalized workout routines to help you achieve fitness goals like muscle gain or body definition. It offers optimized exercises, progress tracking, and the ability to customize routines for home or gym training.

Highlights
  • Personalized workout routines
  • Muscle gain and body definition plans
  • Progress tracking
  • Exercise technique guidance
  • Customizable routines
  • Home and gym training options
Read full description

IT'S NEVER BEEN SO EASY AND FUN TO TRAIN AND MEET YOUR GOALS Trena is an app created by fitness trainers for you to reach your fitness goals such as gaining muscle mass, improving your physical condition or defining your body with routines optimized for your level and created not to be monotonous. WHY USE TRENA? The routines generated by our intelligent algorithm are optimized to stimulate your muscles to the maximum with the best exercises to make your sessions as fun and effective as possible. Also, if you are short on time we have express routines that you can do in less than 60 minutes. With Trena you will be able to: -Follow the exercises intuitively and learn the correct technique -Save the weights of the exercises you perform -Track the time it takes you to do each set, as well as your daily routine -Prioritize a muscle group you want to work -Change the exercises in your routine that you don't like for exercise alternatives CAN I TRAIN AT HOME? Of course! Trena allows you to choose between training at home, at the gym, choose the type of weights or machines you want to use, the days you want to train, among other things. You can train from the comfort of your home at the time you prefer with exercises selected for it. PROGRESS WITH TRENA! Our system assigns you series and repetitions that stimulate your muscles to the maximum according to your initial physical level, but also as you progress and meet the parameters that we will ask you, your routine will progress so that you continue to increase your muscle mass and take you to the next level. This app uses the standard terms of use from Apple: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

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

Screenshots

Trena4 screens
Kaizer4 screens

Verdict

The call

Trena and Kaizer both sit at 4.9 stars, but that hides the real split: 100% of Kaizer's written reviews are positive against 61% of Trena's. On price, rating, ratings volume 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. Trena sells 2 in-app purchases, starting at $4.99 per month and Kaizer sells 11 in-app purchases, starting at $3.99 per 7 days. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for Trena against 5.0 for Kaizer. Both are backed by a comparable volume of ratings — 23 and 9 respectively. Written reviews are what separate them: 61% of Trena's written reviews are positive against 100% of Kaizer's.

UpkeepUpdate frequency

Trena ships an update weekly, Kaizer every 8 days. The most recent releases landed on October 24, 2026 and October 28, 2026 respectively.

Scorecard1 real difference · 9 level
Trena versus Kaizer: the parameters behind the verdict, then further details
ParameterTrenaKaizer
PriceFreeFree
Rating4.9 (23 ratings)5.0 (9 ratings) — better
Positive reviews60.7% of reviews100.0% of reviews — better
Number of ratings23 — better9
Update frequencyWeekly — betterEvery 8 days
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhoneiPhone, iPad — better
Requires iOS16.416.4
Further details — not scored
Size78 MB109 MB
Age rating4+4+
DeveloperAndres VazquezKAIZER

Customer experience

Trena

All ratings17 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews28 reviews
Positive60.7%
Neutral17.9%
Negative21.4%

Kaizer

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

In-app purchases

2 purchases

Trena

Subscriptions2
  • Mensualidad Premium$4.991 Month
  • Six months premium$22.996 Months
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

Questions

Is Trena free?
Trena is free to download, with in-app purchases available.
Is Kaizer free?
Kaizer is free to download, with in-app purchases available.
Which has better reviews, Trena or Kaizer?
Kaizer is rated higher. Trena averages 4.9 out of 5 from 23 ratings, while Kaizer averages 5.0 from 9 ratings.
Do Trena or Kaizer have ads?
Neither Trena nor Kaizer shows ads.
Which is updated more often, Trena or Kaizer?
Trena ships an update weekly, and Kaizer every 8 days. Most recently, Trena was updated on October 24, 2026 and Kaizer on October 28, 2026.

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