# Photronium vs Physics Constants Library

The clearest difference is ads: Photronium at none against Physics Constants Library's shown. Photronium also leads on update cadence (monthly vs every 7 months) and iOS requirement (16.4 vs 18.4). On price, in-app purchases and device support there is nothing between them.

Both are free to download. Photronium sells 1 one-off in-app purchase and Physics Constants Library sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Photronium ships an update monthly, Physics Constants Library every 7 months. The most recent releases landed on October 29, 2026 and October 22, 2026 respectively.

## The numbers

| Metric | Photronium | Physics Constants Library |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (10 ratings)](https://appshunter.io/ios/app/photronium-physics-equations/id1546383517/reviews)** | — |
| Number of ratings | **10** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Monthly** | Every 7 months |
| Monetization | Free with in-app purchases | — |
| Size | 59 MB | 10 MB |
| Requires iOS | **16.4** | 18.4 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Hao Nguyen](https://appshunter.io/developer/1546383519) | [ChatStick Company Limited](https://appshunter.io/developer/1165816085) |

## 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 |


### Physics Constants Library

[App page](https://appshunter.io/ios/app/physics-constants-library/id6751224343)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock All Features | $2.99 | one-time |


## Frequently asked questions

### Is Photronium free?

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

### Is Physics Constants Library free?

Physics Constants Library is free to download, with in-app purchases available.

### Do Photronium or Physics Constants Library have ads?

Physics Constants Library shows ads; Photronium does not.

### Which is updated more often, Photronium or Physics Constants Library?

Photronium ships an update monthly, and Physics Constants Library every 7 months. Most recently, Photronium was updated on October 29, 2026 and Physics Constants Library on October 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.*