# Physical Constants vs Pääsy

The clearest difference is in-app purchases: Physical Constants at none against Pääsy's 2. Physical Constants also leads on iOS requirement (12.0 vs 15.1). Pääsy's advantage is ads (none vs shown) and update cadence (every 3 days vs every 9 months). On price and device support there is nothing between them.

Both are free to download. Pääsy sells 2 in-app purchases, starting at $17.90 per month. Physical Constants asks for nothing beyond the download.

Physical Constants ships an update every 9 months, Pääsy every 3 days. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Physical Constants | Pääsy |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.3 (3 ratings)](https://appshunter.io/ios/app/physical-constants-ml/id837679891/reviews)** | — |
| Number of ratings | **3** | — |
| Positive reviews | 33.3% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | Yes | **No** |
| Update frequency | Every 9 months | **Every 3 days** |
| Monetization | Ad-supported | — |
| Size | 25 MB | 53 MB |
| Requires iOS | **12.0** | 15.1 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Takuya Ishikawa](https://appshunter.io/developer/468311118) | [Valinta Digital Oy](https://appshunter.io/developer/6783481012) |

## What reviewers say

### Physical Constants

[App page](https://appshunter.io/ios/app/physical-constants-ml/id837679891)

Access a comprehensive list of physical constants, organized by category for easy searching. This app supports all AppStore languages and allows users to report corrections via email.

**Highlights:** Physical constants database, Categorized by topic, Search functionality, Multi-language support, User feedback for corrections

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

**In-app purchases:** none


### Pääsy

[App page](https://appshunter.io/ios/app/paasy/id6783481010)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pääsy+ | $17.90 | per month |
| Pääsy+ | $22.99 | per month |


## Frequently asked questions

### Is Physical Constants free?

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

### Is Pääsy free?

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

### Do Physical Constants or Pääsy have ads?

Physical Constants shows ads; Pääsy does not.

### Which is updated more often, Physical Constants or Pääsy?

Physical Constants ships an update every 9 months, and Pääsy every 3 days. Most recently, Physical Constants was updated on October 26, 2026 and Pääsy on October 25, 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.*