# Chess Codex vs 9BLOCK

The clearest difference is ads: 9BLOCK at none against Chess Codex's shown. Chess Codex's advantage is update cadence (every 3 days vs every 3 weeks). On price, in-app purchases, device support and iOS requirement there is nothing between them.

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

Chess Codex ships an update every 3 days, 9BLOCK every 3 weeks. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Chess Codex | 9BLOCK |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (3 ratings)](https://appshunter.io/ios/app/9block-memory-game/id6785684483/reviews)** |
| Number of ratings | — | **3** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | **Every 3 days** | Every 3 weeks |
| Monetization | — | Free |
| Size | 36 MB | 23 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Vince Lubbers](https://appshunter.io/developer/1889839785) | [Duncan Fondren](https://appshunter.io/developer/6785684485) |

## What reviewers say

### Chess Codex

[App page](https://appshunter.io/ios/app/chess-codex/id6778615817)

**Features:** macOS Compatibility

**In-app purchases:** none


### 9BLOCK

[App page](https://appshunter.io/ios/app/9block-memory-game/id6785684483)

This minimalist game challenges your visual recall and focus by requiring you to memorize the order of numbers on nine blocks. It's a quick, engaging experience that's easy to learn but difficult to master.

**Highlights:** Memorize number order, Tap numbers 1-9, Improve longest streak, Ranked progression, Customize blocks and reveal time, Track personal bests

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

**In-app purchases:** none


## Frequently asked questions

### Is Chess Codex free?

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

### Is 9BLOCK free?

9BLOCK is free to download, with no in-app purchases.

### Do Chess Codex or 9BLOCK have ads?

Chess Codex shows ads; 9BLOCK does not.

### Which is updated more often, Chess Codex or 9BLOCK?

Chess Codex ships an update every 3 days, and 9BLOCK every 3 weeks. Most recently, Chess Codex was updated on November 5, 2026 and 9BLOCK on October 31, 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.*