# KPD vs Codon One

The clearest difference is review sentiment: Codon One at 76% against KPD's 22%. Codon One also leads on update cadence (every 3 weeks vs every 5 months). KPD's advantage is in-app purchases (none vs 7). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Codon One sells 7 one-off in-app purchases. KPD asks for nothing beyond the download.

KPD ships an update every 5 months, Codon One every 3 weeks. The most recent releases landed on October 21, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | KPD | Codon One |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[4.5 (24 ratings)](https://appshunter.io/ios/app/codon-one-biology-study/id1517313390/reviews)** |
| Number of ratings | — | **24** |
| Positive reviews | 22.2% of reviews | **76.5% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 months | **Every 3 weeks** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 10 MB | 277 MB |
| Requires iOS | 16.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 12+ | 4+ |
| Developer | [НОУ МЦНМО](https://appshunter.io/developer/1235476259) | [Daniel Gebert](https://appshunter.io/developer/1517313389) |

## What reviewers say

### KPD

[App page](https://appshunter.io/ios/app/kpd-bio/id1229570219)

This app provides a comprehensive Russian-language electronic version of a leading biology textbook, ideal for high school students and teachers. It includes supplementary materials for practice and scientific article analysis, offering structured learning from basic to advanced concepts.

**Highlights:** Russian electronic textbook, Student Study Guide included, Inquiry in Action guide, University-level biology content, Illustrations and diagrams, Self-check questions and tasks, Electronic glossary search

**Features:** macOS Compatibility

**In-app purchases:** none


### Codon One

[App page](https://appshunter.io/ios/app/codon-one-biology-study/id1517313390)

Master molecular biology, genetics, evolution, and life chemistry through interactive modules and quizzes. Explore essential concepts with clear diagrams and concise explanations. Includes helpful tools for sequence analysis and genetic code reference.

**Highlights:** Interactive learning modules, Quick quizzes for comprehension, Clear diagrams and plain language, Molecule reference guide, Sequence analysis tools, Genetic code exploration

**Features:** Family Sharing, Vision Pro support

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Module 1: Chemistry of Life | Free | one-time |
| Module 2: Genetics | $2.99 | one-time |
| Module 3: Evolution | $2.99 | one-time |
| Module 4: Science History | $2.99 | one-time |
| Module 5: Cell Biology | $2.99 | one-time |
| Module 6: Development | $2.99 | one-time |
| Unlock All | $8.99 | one-time |


## Frequently asked questions

### Is KPD free?

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

### Is Codon One free?

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

### Do KPD or Codon One have ads?

Neither KPD nor Codon One shows ads.

### Which is updated more often, KPD or Codon One?

KPD ships an update every 5 months, and Codon One every 3 weeks. Most recently, KPD was updated on October 21, 2026 and Codon One on October 10, 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.*