# Power Flex vs Kaizer

The clearest difference is in-app purchases: Power Flex at none against Kaizer's 11. Power Flex also leads on iOS requirement (12.0 vs 16.4). Kaizer's advantage is update cadence (every 8 days vs every 3 months). On price, ads and device support there is nothing between them.

Both are free to download. Kaizer sells 11 in-app purchases, starting at $3.99 per 7 days. Power Flex asks for nothing beyond the download.

Power Flex ships an update every 3 months, Kaizer every 8 days. The most recent releases landed on October 5, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Power Flex | Kaizer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (9 ratings)](https://appshunter.io/ios/app/kaizer-your-personal-trainer/id6748926600/reviews)** |
| Number of ratings | — | **9** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 8 days** |
| Monetization | — | Freemium |
| Size | 61 MB | 109 MB |
| Requires iOS | **12.0** | 16.4 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [Sergio Andres Soto Arroyave](https://appshunter.io/developer/1705489729) | [KAIZER](https://appshunter.io/developer/1828054877) |

## What reviewers say

### Power Flex

[App page](https://appshunter.io/ios/app/power-flex/id6745300878)

**Features:** macOS Compatibility

**In-app purchases:** none


### Kaizer

[App page](https://appshunter.io/ios/app/kaizer-your-personal-trainer/id6748926600)

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:** macOS Compatibility, Vision Pro support

**In-app purchases (11)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Weekly | $3.99 | per 7 days |
| Pro Monthly | $8.99 | per month |
| Trainer Plan — $39.99 | $39.99 | per month |
| Pro Yearly | $39.99 | per year |
| Trainer Plan — $59.99 | $59.99 | per month |
| Trainer Plan — $79.99 | $79.99 | per month |
| Trainer Plan — $99.99 | $99.99 | per month |
| Trainer Plan — $109.99 | $109.99 | per month |
| Trainer Plan — $129.99 | $129.99 | per month |
| Trainer Plan — $159.99 | $159.99 | per month |
| Pro Lifetime | $89.99 | one-time |


## Frequently asked questions

### Is Power Flex free?

Power Flex is free to download, with no in-app purchases.

### Is Kaizer free?

Kaizer is free to download, with in-app purchases available.

### Do Power Flex or Kaizer have ads?

Neither Power Flex nor Kaizer shows ads.

### Which is updated more often, Power Flex or Kaizer?

Power Flex ships an update every 3 months, and Kaizer every 8 days. Most recently, Power Flex was updated on October 5, 2026 and Kaizer on October 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*