# Decoder

> Mastermind game solver that reduces possible solutions with each guess. (iPhone/iPad app by Edwin Hou.)

- Source: https://appshunter.io/ios/app/decoder/id294816947 (this page in markdown: same URL + `.md`)
- Developer: [Edwin Hou](https://appshunter.io/developer/292240393)
- Category: Games, Reference, Board
- Price: Free
- Rating: 1.20/5 from 5 App Store ratings · 5 written reviews indexed
- Age rating: 4+
- Requires: iOS 7.0 · 1 MB
- Languages: American English
- Released: 2008-10-29
- Data updated: 2026-06-05
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/decoder/id294816947/reviews.md

## What is Decoder?

This is NOT another mastermind look alike game. However, if you like to play mastermind, you would want to get this application. This application helps you solve the mastermind game.

Use the first picker to select a guess. Then select the score you got for that guess on the second picker and click Decode. The application will determine the remaining possible solutions. The number of remaining possible solution is shown on the toolbar. Repeat the above steps until one solution is left.

## Key features

- Mastermind game solver
- Input guesses and scores
- Reduces possible solutions
- Guides to single solution

## Recent user reviews (5 of 5)

All indexed reviews: https://appshunter.io/ios/app/decoder/id294816947/reviews.md

### 1/5 — Shame

*2019-08-17, version 1.5*

If the instructions gave any clue as to the purpose it might, only might, help

### 1/5 — Vague instructions

*2019-02-24, version 1.5*

The instructions are vague and make no sense. I tried to figure it out but got frustrated and deleted it.

### 1/5 — No instructions

*2019-02-10, version 1.5*

This game has no instructions!! Crazy. Will delete

### 2/5 — Bad instructions

*2019-01-22, version 1.5*

The instructions are not clear and no examples are given.

### 1/5 — Rubbish

*2012-03-23, version 1.3.1*

This game is rubbish the instructions are pants

## Frequently asked questions about Decoder

### How does Decoder help me solve Mastermind?

Decoder helps you solve Mastermind by taking your guesses and the resulting scores (number of correct colors in the correct position and number of correct colors in the wrong position) and calculating the remaining possible solutions. You input your progress step-by-step until only one solution is left.

### Is Decoder a Mastermind game itself?

No, Decoder is not a Mastermind game. It is a helper application designed to assist you in solving the Mastermind logic game by providing logical deductions based on your inputs.

### What devices does Decoder support?

Decoder is available for iPhone and iPod devices. It was last updated on May 12, 2014, with version 1.5.

### What is the age rating for Decoder?

Decoder has an age rating of 4+. This indicates it is suitable for children aged 4 and above.

### How often is Decoder updated?

Decoder was last updated on May 12, 2014. The app has not received updates since then.

### Does Decoder have ads?

No, Decoder does not contain advertisements. It is a free application without any in-app purchases or ads.

### What is the user rating for Decoder?

Decoder has a user rating of 1.2 stars based on 5 ratings. This suggests a generally negative user reception.

### Can Decoder be played offline?

As Decoder is a helper tool for a logic game, its core functionality of calculating solutions based on user input does not require an internet connection, suggesting it can be used offline.

## Version history (last 5 releases)

### 1.5 — 2014-05-12

Updated for iOS 7.

### 1.4.2 — 2013-02-02

Bug fixed.

### 1.4.1 — 2012-12-08

Fixed icon and rotation bug. Improved picker appearance.

### 1.4 — 2012-11-28

iOS 6.0 ready. Supports iPhone 5.

### 1.3.1 — 2011-11-28

Fixed error with About button.

## Apps similar to Decoder

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Peer Images Wear - Watch Game](https://appshunter.io/ios/app/peer-images-wear-watch-game/id1465627023) | 4.6 (7) | $0.99 | Games |
| [Color Sudoku: Logic Blocks](https://appshunter.io/ios/app/color-sudoku-logic-blocks/id6499296812) | 4.8 (9) | Free | Games |
| [Data Diggers](https://appshunter.io/ios/app/data-diggers/id6449879442) | 3.0 (4) | Free | Games |
| [Labyrinth: The War on Terror](https://appshunter.io/ios/app/labyrinth-the-war-on-terror/id1438485859) | 4.3 (22) | $9.99 | Games |
| [Concordia: Digital Edition](https://appshunter.io/ios/app/concordia-digital-edition/id1536417255) | 3.6 (85) | $9.99 | Games |
| [Block Puzzle - Brain Test, IQ](https://appshunter.io/ios/app/block-puzzle-brain-test-iq/id1577795067) | 5.0 (2) | Free | Games |

## More apps by Edwin Hou

- [ISO 3166](https://appshunter.io/ios/app/iso-3166/id298599095)
- [〇 Sudoku](https://appshunter.io/ios/app/sudoku/id594527629)

All apps by Edwin Hou: https://appshunter.io/developer/292240393

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-05.*