# PassFinder vs (Open Source) Mental Math

PassFinder and (Open Source) Mental Math both sit at 3.1 stars, but that hides the real split: 39% of PassFinder's written reviews are positive against 0% of (Open Source) Mental Math's. PassFinder also leads on ratings volume (30 vs 2). (Open Source) Mental Math's advantage is iOS requirement (16.4 vs 18.0). On price, rating, update cadence and ads there is nothing between them.

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

On the App Store both sit at effectively the same score — 3.1 for PassFinder against 3.0 for (Open Source) Mental Math. That said, the two scores are not equally well evidenced: PassFinder has 30 ratings behind it against 2, so its average is the more settled of the two. Written reviews are what separate them: 39% of PassFinder's written reviews are positive against 0% of (Open Source) Mental Math's.

PassFinder ships an update every 3 months, (Open Source) Mental Math every 2 months. The most recent releases landed on September 28, 2026 and September 19, 2026 respectively.

## The numbers

| Metric | PassFinder | (Open Source) Mental Math |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.1 (30 ratings)](https://appshunter.io/ios/app/passfinder/id721125800/reviews)** | [3.0 (2 ratings)](https://appshunter.io/ios/app/open-source-mental-math/id6788418444/reviews) |
| Number of ratings | **30** | 2 |
| Positive reviews | **39.0% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 2 months** |
| Monetization | Free | Free |
| Size | 5 MB | 40 MB |
| Requires iOS | 18.0 | **16.4** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Christian Hansen](https://appshunter.io/developer/721033532) | [AHMET EMRE DEDELER](https://appshunter.io/developer/1870913629) |

## What reviewers say

### PassFinder

[App page](https://appshunter.io/ios/app/passfinder/id721125800)

Track the International Space Station's visible passes over your location. Receive precise timing information to observe the ISS with the naked eye.

**Highlights:** ISS pass tracking, Visible pass notifications, Naked-eye observation guidance, Location-based timing

**Features:** macOS Compatibility

**In-app purchases:** none


### (Open Source) Mental Math

[App page](https://appshunter.io/ios/app/open-source-mental-math/id6788418444)

This application offers a free, open-source platform for practicing mental arithmetic. It features timed tests, custom drills, and a comprehensive library of mental math tricks. All content is available offline without ads or paywalls.

**Highlights:** Timed arithmetic tests, Customizable drills, Mental math tricks library, Offline progress tracking, Multiple operation types, Fast session interface

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

**In-app purchases:** none


## Frequently asked questions

### Is PassFinder free?

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

### Is (Open Source) Mental Math free?

(Open Source) Mental Math is free to download, with no in-app purchases.

### Which has better reviews, PassFinder or (Open Source) Mental Math?

PassFinder is rated higher. PassFinder averages 3.1 out of 5 from 30 ratings, while (Open Source) Mental Math averages 3.0 from 2 ratings.

### Do PassFinder or (Open Source) Mental Math have ads?

Neither PassFinder nor (Open Source) Mental Math shows ads.

### Which is updated more often, PassFinder or (Open Source) Mental Math?

PassFinder ships an update every 3 months, and (Open Source) Mental Math every 2 months. Most recently, PassFinder was updated on September 28, 2026 and (Open Source) Mental Math on September 19, 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.*