# PJFFfree vs Triangle3

The clearest difference is review sentiment: PJFFfree at 100% against Triangle3's 40%. PJFFfree also leads on price (Free vs $3.99). Triangle3's advantage is ads (none vs shown). On update cadence, in-app purchases, device support and iOS requirement there is nothing between them.

PJFFfree is free to download; Triangle3 costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Both ship on a similar rhythm, roughly every 5 weeks. The most recent releases landed on October 8, 2026 and October 12, 2026 respectively.

## The numbers

| Metric | PJFFfree | Triangle3 |
| --- | --- | --- |
| Price | **Free** | $3.99 |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/pjfffree/id629958775/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | **100.0% of reviews** | 40.0% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 5 weeks | Every 5 weeks |
| Monetization | **Ad-supported** | Paid |
| Size | 7 MB | 7 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [sigeyosi kanenishi](https://appshunter.io/developer/629958778) | [ryo sasaki](https://appshunter.io/developer/318552526) |

## 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


### Triangle3

[App page](https://appshunter.io/ios/app/triangle3/id1643788233)

This app provides advanced calculation tools for field work, specializing in right and unequal triangles. It supports complex shapes like cones, pipes, and screw wings, with AR visualization for floor plans. It also includes standard calculator functions and memory features.

**Highlights:** Right and unequal triangle calculations, Complex shape development (cones, pipes, etc.), Augmented Reality (AR) floor plan visualization, Standard calculator functions with memory, Trigonometric and cosine theorem calculations, PCD and screw wing calculations

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is PJFFfree free?

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

### Is Triangle3 free?

Triangle3 costs $3.99, with no in-app purchases.

### Do PJFFfree or Triangle3 have ads?

PJFFfree shows ads; Triangle3 does not.

### Which is updated more often, PJFFfree or Triangle3?

PJFFfree ships an update every 5 weeks, and Triangle3 every 5 weeks. Most recently, PJFFfree was updated on October 8, 2026 and Triangle3 on October 12, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*