# Mack Masters Competition vs DEC Opcodes

The clearest difference is in-app purchases: Mack Masters Competition at none against DEC Opcodes's 1. DEC Opcodes's advantage is update cadence (every 8 days vs every 42 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. DEC Opcodes sells 1 one-off in-app purchase. Mack Masters Competition asks for nothing beyond the download.

Mack Masters Competition ships an update every 42 months, DEC Opcodes every 8 days. The most recent releases landed on October 15, 2026 and October 7, 2026 respectively.

## The numbers

| Metric | Mack Masters Competition | DEC Opcodes |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (3 ratings)](https://appshunter.io/ios/app/dec-opcodes/id6760246055/reviews)** |
| Number of ratings | — | **3** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 42 months | **Every 8 days** |
| Monetization | — | Free |
| Size | 36 MB | 42 MB |
| Requires iOS | **17.6** | 18.0 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Mack Trucks, Inc.](https://appshunter.io/developer/421834196) | [John Kennedy](https://appshunter.io/developer/284943103) |

## What reviewers say

### Mack Masters Competition

[App page](https://appshunter.io/ios/app/mack-masters-competition/id6446115683)

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

**In-app purchases:** none


### DEC Opcodes

[App page](https://appshunter.io/ios/app/dec-opcodes/id6760246055)

Explore the instruction sets of legendary DEC computers like the PDP and VAX. This app provides detailed information on each instruction, historical context, and interactive lessons. Discover the machines that shaped modern computing.

**Highlights:** Instruction set reference, Historical context and photos, System specifications, Interactive assembly lessons, Search and filtering, Customizable themes, Simple assembler

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Buy Me a Coffee | $0.99 | one-time |


## Frequently asked questions

### Is Mack Masters Competition free?

Mack Masters Competition is free to download, with no in-app purchases.

### Is DEC Opcodes free?

DEC Opcodes is free to download, with in-app purchases available.

### Do Mack Masters Competition or DEC Opcodes have ads?

Neither Mack Masters Competition nor DEC Opcodes shows ads.

### Which is updated more often, Mack Masters Competition or DEC Opcodes?

Mack Masters Competition ships an update every 42 months, and DEC Opcodes every 8 days. Most recently, Mack Masters Competition was updated on October 15, 2026 and DEC Opcodes on October 7, 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.*