# PJFFfree vs Trigonometric Calculation

PJFFfree and Trigonometric Calculation are too close to call on the numbers: across 6 compared parameters — price, update cadence, ads and in-app purchases among them — neither pulls far enough ahead to decide it. What separates them is feature set and interface, not measurable difference.

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

PJFFfree ships an update every 5 weeks, Trigonometric Calculation every 6 weeks. The most recent releases landed on September 22, 2026 and May 16, 2026 respectively.

## The numbers

| Metric | PJFFfree | Trigonometric Calculation |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/pjfffree/id629958775/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | Yes | Yes |
| Update frequency | **Every 5 weeks** | Every 6 weeks |
| Monetization | Ad-supported | — |
| Size | 7 MB | 5 MB |
| Requires iOS | **15.0** | 15.5 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [sigeyosi kanenishi](https://appshunter.io/developer/629958778) | [Risako Asai](https://appshunter.io/developer/1671273580) |

## What reviewers say

### PJFFfree

[App page](https://appshunter.io/ios/app/pjfffree/id629958775)

This app serves as a manual for piping parts, focusing on Japanese specifications. It lists commonly used items based on manufacturer data and public dimension tables, with all measurements in millimeters.

**Highlights:** Piping parts manual, Japanese specifications, Commonly used parts listing, Manufacturer data integration, Millimeter measurements, JIS standards compliance

**Features:** macOS Compatibility

**In-app purchases:** none


### Trigonometric Calculation

[App page](https://appshunter.io/ios/app/trigonometric-calculation/id1636196284)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is PJFFfree free?

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

### Is Trigonometric Calculation free?

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

### Do PJFFfree or Trigonometric Calculation have ads?

Both PJFFfree and Trigonometric Calculation show ads.

### Which is updated more often, PJFFfree or Trigonometric Calculation?

PJFFfree ships an update every 5 weeks, and Trigonometric Calculation every 6 weeks. Most recently, PJFFfree was updated on September 22, 2026 and Trigonometric Calculation on May 16, 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.*