# Sudoku Checker vs Quick3D CAD Viewer

The clearest difference is ads: Sudoku Checker at none against Quick3D CAD Viewer's shown. Sudoku Checker also leads on iOS requirement (9.0 vs 18.6). Quick3D CAD Viewer's advantage is update cadence (every 2 weeks vs every 2 months). On price, in-app purchases and device support there is nothing between them.

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

Sudoku Checker ships an update every 2 months, Quick3D CAD Viewer every 2 weeks. The most recent releases landed on October 24, 2026 and October 29, 2026 respectively.

## The numbers

| Metric | Sudoku Checker | Quick3D CAD Viewer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (4 ratings)](https://appshunter.io/ios/app/sudoku-checker/id1458321132/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 85.7% of reviews | — |
| In-app purchases | No | No |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | **Every 2 weeks** |
| Monetization | Free | — |
| Size | 23 MB | 28 MB |
| Requires iOS | **9.0** | 18.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Atsuo Kazama](https://appshunter.io/developer/1442822891) | [Ryo Tazaki](https://appshunter.io/developer/6814366399) |

## What reviewers say

### Sudoku Checker

[App page](https://appshunter.io/ios/app/sudoku-checker/id1458321132)

This app allows you to input numbers from a physical Sudoku puzzle and verifies its validity. It identifies single solutions, multiple solutions, or contradictions. The app displays your input in black and derived numbers in gray.

**Highlights:** Input hand-written Sudoku numbers, Displays derived numbers in gray, Verifies puzzle validity, Detects single/multiple solutions, Identifies contradictions

**Features:** macOS Compatibility

**In-app purchases:** none


### Quick3D CAD Viewer

[App page](https://appshunter.io/ios/app/quick3d-cad-viewer/id6816122073)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Sudoku Checker free?

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

### Is Quick3D CAD Viewer free?

Quick3D CAD Viewer is free to download, with no in-app purchases.

### Do Sudoku Checker or Quick3D CAD Viewer have ads?

Quick3D CAD Viewer shows ads; Sudoku Checker does not.

### Which is updated more often, Sudoku Checker or Quick3D CAD Viewer?

Sudoku Checker ships an update every 2 months, and Quick3D CAD Viewer every 2 weeks. Most recently, Sudoku Checker was updated on October 24, 2026 and Quick3D CAD Viewer on October 29, 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.*