# Photronium vs BitSpinner

The clearest difference is in-app purchases: BitSpinner at none against Photronium's 1. Photronium's advantage is update cadence (monthly vs every 4 months) and iOS requirement (16.4 vs 26.0). On price, ads and device support there is nothing between them.

Both are free to download. Photronium sells 1 one-off in-app purchase. BitSpinner asks for nothing beyond the download.

Photronium ships an update monthly, BitSpinner every 4 months. The most recent releases landed on October 6, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Photronium | BitSpinner |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (8 ratings)](https://appshunter.io/ios/app/photronium-physics-equations/id1546383517/reviews)** | — |
| Number of ratings | **8** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Monthly** | Every 4 months |
| Monetization | Free with in-app purchases | — |
| Size | 59 MB | 8 MB |
| Requires iOS | **16.4** | 26.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Hao Nguyen](https://appshunter.io/developer/1546383519) | [Robert Lis](https://appshunter.io/developer/567589617) |

## What reviewers say

### Photronium

[App page](https://appshunter.io/ios/app/photronium-physics-equations/id1546383517)

Access over 360 physics equations with clear explanations and powerful search tools. Test your knowledge with custom quizzes and learn offline anywhere, anytime. This educational reference is designed for learners of all levels.

**Highlights:** 360+ physics equations, Offline access, Intelligent Search, Symbol Search, Customizable quizzes, Bookmarking

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Multicolored Bookmarks | $0.99 | one-time |


### BitSpinner

[App page](https://appshunter.io/ios/app/bitspinner/id6761688095)

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

**In-app purchases:** none


## Frequently asked questions

### Is Photronium free?

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

### Is BitSpinner free?

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

### Do Photronium or BitSpinner have ads?

Neither Photronium nor BitSpinner shows ads.

### Which is updated more often, Photronium or BitSpinner?

Photronium ships an update monthly, and BitSpinner every 4 months. Most recently, Photronium was updated on October 6, 2026 and BitSpinner on October 14, 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.*