# Triangle3 vs Weld Positioner RPM

The clearest difference is price: Weld Positioner RPM at Free against Triangle3's $3.99. Weld Positioner RPM also leads on update cadence (every 2 days vs every 5 weeks). Triangle3's advantage is in-app purchases (none vs 2) and iOS requirement (15.0 vs 26.2). On ads and device support there is nothing between them.

Weld Positioner RPM is free to download; Triangle3 costs $3.99 up front. Weld Positioner RPM sells 2 in-app purchases, starting at $3.99 per month. Triangle3 asks for nothing beyond the download.

Triangle3 ships an update every 5 weeks, Weld Positioner RPM every 2 days. The most recent releases landed on October 30, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | Triangle3 | Weld Positioner RPM |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Positive reviews | 40.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 weeks | **Every 2 days** |
| Monetization | Paid | — |
| Size | 7 MB | 8 MB |
| Requires iOS | **15.0** | 26.2 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 17+ |
| Developer | [ryo sasaki](https://appshunter.io/developer/318552526) | [Masashi Konno](https://appshunter.io/developer/1877017984) |

## What reviewers say

### 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


### Weld Positioner RPM

[App page](https://appshunter.io/ios/app/weld-positioner-rpm/id6767473393)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weld Positioner Monthly | $3.99 | per month |
| Weld Positioner Yearly | $39.99 | per year |


## Frequently asked questions

### Is Triangle3 free?

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

### Is Weld Positioner RPM free?

Weld Positioner RPM is free to download, with in-app purchases available.

### Do Triangle3 or Weld Positioner RPM have ads?

Neither Triangle3 nor Weld Positioner RPM shows ads.

### Which is updated more often, Triangle3 or Weld Positioner RPM?

Triangle3 ships an update every 5 weeks, and Weld Positioner RPM every 2 days. Most recently, Triangle3 was updated on October 30, 2026 and Weld Positioner RPM on October 28, 2026.

---

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