# Feynman rules vs Operators Puzzle Number Games

Feynman rules and Operators Puzzle Number Games are too close to call on the numbers: across 5 compared parameters — price, ads, in-app purchases and device support among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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

## The numbers

| Metric | Feynman rules | Operators Puzzle Number Games |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | — | Every 3 months |
| Size | 6 MB | 28 MB |
| Requires iOS | **16.0** | 17.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Sungjun Kim](https://appshunter.io/developer/1602461985) | [Takatoshi Ichige](https://appshunter.io/developer/1717609832) |

## What reviewers say

### Feynman rules

[App page](https://appshunter.io/ios/app/feynman-rules/id6478752222)

**Features:** macOS Compatibility

**In-app purchases:** none


### Operators Puzzle Number Games

[App page](https://appshunter.io/ios/app/operators-puzzle-number-games/id6651841503)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Feynman rules free?

Feynman rules is free to download, with no in-app purchases.

### Is Operators Puzzle Number Games free?

Operators Puzzle Number Games is free to download, with no in-app purchases.

### Do Feynman rules or Operators Puzzle Number Games have ads?

Neither Feynman rules nor Operators Puzzle Number Games shows ads.

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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.*