# Quantum 3 vs STEM Defense

The clearest difference is price: Quantum 3 at Free against STEM Defense's $6.99. Quantum 3 also leads on iOS requirement (12.0 vs 15.0). STEM Defense's advantage is update cadence (every 3 days vs every 16 months). On ads, in-app purchases and device support there is nothing between them.

Quantum 3 is free to download; STEM Defense costs $6.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Quantum 3 ships an update every 16 months, STEM Defense every 3 days. The most recent releases landed on October 3, 2026 and August 22, 2026 respectively.

## The numbers

| Metric | Quantum 3 | STEM Defense |
| --- | --- | --- |
| Price | **Free** | $6.99 |
| Rating | **[5.0 (15 ratings)](https://appshunter.io/ios/app/quantum-3/id1406630529/reviews)** | — |
| Number of ratings | **15** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 16 months | **Every 3 days** |
| Monetization | Free | — |
| Size | 124 MB | 411 MB |
| Requires iOS | **12.0** | 15.0 |
| Devices | iPhone, iPad, iPod | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 9+ |
| Developer | [Brian Winn](https://appshunter.io/developer/487088992) | [Andrea Carlomaria Sertorio](https://appshunter.io/developer/1465623599) |

## What reviewers say

### Quantum 3

[App page](https://appshunter.io/ios/app/quantum-3/id1406630529)

An educational match-3 game that blends fun gameplay with quantum physics concepts. Players match quarks to build subatomic particles and learn about fundamental physics mysteries. It's a great introduction to particle physics for all ages.

**Highlights:** Match-3 gameplay, Learn quantum physics, Build subatomic particles, Explore fundamental physics, Puzzle-solving mechanics

**Features:** macOS Compatibility

**In-app purchases:** none


### STEM Defense

[App page](https://appshunter.io/ios/app/stem-defense/id6502572873)

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Quantum 3 free?

Quantum 3 is free to download, with no in-app purchases.

### Is STEM Defense free?

STEM Defense costs $6.99, with no in-app purchases.

### Do Quantum 3 or STEM Defense have ads?

Neither Quantum 3 nor STEM Defense shows ads.

### Which is updated more often, Quantum 3 or STEM Defense?

Quantum 3 ships an update every 16 months, and STEM Defense every 3 days. Most recently, Quantum 3 was updated on October 3, 2026 and STEM Defense on August 22, 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.*