# Brain Training Calculation Master vs P21

The clearest difference is ads: P21 at none against Brain Training Calculation Master's shown. P21 also leads on monetization model (free vs ad-supported) and update cadence (every 6 weeks vs every 3 months). Brain Training Calculation Master's advantage is iOS requirement (7.0 vs 11.0). On price, rating, ratings volume and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

On the App Store both sit at effectively the same score — 5.0 for Brain Training Calculation Master against 5.0 for P21. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

Brain Training Calculation Master ships an update every 3 months, P21 every 6 weeks. The most recent releases landed on August 20, 2026 and July 6, 2026 respectively.

## The numbers

| Metric | Brain Training Calculation Master | P21 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (1 ratings)](https://appshunter.io/ios/app/brain-training-calculation-master/id702231884/reviews) | [5.0 (1 ratings)](https://appshunter.io/ios/app/p21/id1453823561/reviews) |
| Number of ratings | 1 | 1 |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 3 months | **Every 6 weeks** |
| Monetization | Ad-supported | **Free** |
| Size | 16 MB | 226 MB |
| Requires iOS | **7.0** | 11.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Takahiro Iwatani](https://appshunter.io/developer/702231887) | [CAVES BOOKS LTD.](https://appshunter.io/developer/547924599) |

## What reviewers say

### Brain Training Calculation Master

[App page](https://appshunter.io/ios/app/brain-training-calculation-master/id702231884)

Enhance your mathematical skills with engaging practice sessions. This app offers customizable drills for addition, subtraction, and multiplication, with options for digit count and question quantity. It also features unique numeral systems to further challenge your brain.

**Highlights:** Addition, subtraction, and multiplication practice, Selectable digit count (1-4 digits), Customizable question quantity (10, 30, 50, 100), Adjustable button arrangement, Multiple numeral systems (standard, Chinese, Japanese, English)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### P21

[App page](https://appshunter.io/ios/app/p21/id1453823561)

This educational app supports a four-level phonics series for young learners. It offers audio tracks, videos, flashcards, and games to help children build foundational skills in phonological awareness, reading, and spelling.

**Highlights:** Audio tracks from student books, Educational videos, Keyword flashcards, Phonics games, Progress tracking

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Brain Training Calculation Master free?

Brain Training Calculation Master is free to download, with no in-app purchases.

### Is P21 free?

P21 is free to download, with no in-app purchases.

### Which has better reviews, Brain Training Calculation Master or P21?

Brain Training Calculation Master and P21 are both rated 5.0 out of 5 on the App Store, from 1 and 1 ratings respectively.

### Do Brain Training Calculation Master or P21 have ads?

Brain Training Calculation Master shows ads; P21 does not.

### Which is updated more often, Brain Training Calculation Master or P21?

Brain Training Calculation Master ships an update every 3 months, and P21 every 6 weeks. Most recently, Brain Training Calculation Master was updated on August 20, 2026 and P21 on July 6, 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.*