# Matrix math calculator vs PDF Watch Viewer

The clearest difference is in-app purchases: Matrix math calculator at none against PDF Watch Viewer's 1. Matrix math calculator also leads on iOS requirement (13.0 vs 15.0). PDF Watch Viewer's advantage is review sentiment (13% vs 0%). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. PDF Watch Viewer sells 1 one-off in-app purchase. Matrix math calculator asks for nothing beyond the download.

Matrix math calculator ships an update every 3 months, PDF Watch Viewer every 2 months. The most recent releases landed on October 25, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Matrix math calculator | PDF Watch Viewer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.5 (2 ratings)](https://appshunter.io/ios/app/matrix-math-calculator/id993273855/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 0.0% of reviews | **13.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 2 months** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 52 MB | 10 MB |
| Requires iOS | **13.0** | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPod, Apple Watch |
| Age rating | 4+ | 4+ |
| Developer | [camilo arcila](https://appshunter.io/developer/993049913) | [Stefano Russello](https://appshunter.io/developer/543198306) |

## What reviewers say

### Matrix math calculator

[App page](https://appshunter.io/ios/app/matrix-math-calculator/id993273855)

Perform various matrix operations including addition, subtraction, and multiplication. Calculate the transposed matrix, adjoint, inverse, determinant, and rank. Supports matrices of any size (MxN).

**Highlights:** Matrix Addition, Matrix Subtraction, Matrix Multiplication, Transposed Matrix, Adjoint Matrix, Inverse Matrix, Determinant Calculation, Rank Calculation

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

**In-app purchases:** none


### PDF Watch Viewer

[App page](https://appshunter.io/ios/app/pdf-watch-viewer/id1346356339)

View PDF documents directly on your Apple Watch without needing your iPhone. Easily transfer files from your web browser, iCloud, email, or messaging apps to your wrist for convenient access.

**Highlights:** View PDFs on Apple Watch, Transfer files from iPhone, Add PDFs from web browser, Add PDFs from iCloud, Add PDFs from email/messenger

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited PDF | $1.99 | one-time |


## Frequently asked questions

### Is Matrix math calculator free?

Matrix math calculator is free to download, with no in-app purchases.

### Is PDF Watch Viewer free?

PDF Watch Viewer is free to download, with in-app purchases available.

### Do Matrix math calculator or PDF Watch Viewer have ads?

Neither Matrix math calculator nor PDF Watch Viewer shows ads.

### Which is updated more often, Matrix math calculator or PDF Watch Viewer?

Matrix math calculator ships an update every 3 months, and PDF Watch Viewer every 2 months. Most recently, Matrix math calculator was updated on October 25, 2026 and PDF Watch Viewer on October 24, 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.*