# Scales HD vs Architects Ruler

The clearest difference is price: Architects Ruler at Free against Scales HD's $3.99. Architects Ruler also leads on update cadence (every 3 months vs every 95 months). Scales HD's advantage is in-app purchases (none vs 1) and device support (3 vs 1). On ads there is nothing between them.

Architects Ruler is free to download; Scales HD costs $3.99 up front. Architects Ruler sells 1 one-off in-app purchase. Scales HD asks for nothing beyond the download.

Scales HD ships an update every 95 months, Architects Ruler every 3 months. The most recent releases landed on November 1, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | Scales HD | Architects Ruler |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | **[4.2 (5 ratings)](https://appshunter.io/ios/app/scales-hd/id418843481/reviews)** | — |
| Number of ratings | **5** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 95 months | **Every 3 months** |
| Monetization | Paid | — |
| Size | 7 MB | 4 MB |
| Requires iOS | **15.0** | 26.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Marcelo Mejia Cobo](https://appshunter.io/developer/365496933) | [Gijs Raggers](https://appshunter.io/developer/1438841415) |

## What reviewers say

### Scales HD

[App page](https://appshunter.io/ios/app/scales-hd/id418843481)

This app provides a digital architectural and engineering scale ruler with various US and Metric scales. It includes tools like a tape measure and spirit level, with options to flip scales and lock scrolling. Control your music library directly from the app.

**Highlights:** Architectural US Scales, Engineering US Scales, Metric SI Scales, Tape Measure Tool, Spirit Level Tool, Flip Scales Option, Music Control

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

**In-app purchases:** none


### Architects Ruler

[App page](https://appshunter.io/ios/app/architects-ruler/id6755367822)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Lifetime scales menu | $0.99 | one-time |


## Frequently asked questions

### Is Scales HD free?

Scales HD costs $3.99, with no in-app purchases.

### Is Architects Ruler free?

Architects Ruler is free to download, with in-app purchases available.

### Do Scales HD or Architects Ruler have ads?

Neither Scales HD nor Architects Ruler shows ads.

### Which is updated more often, Scales HD or Architects Ruler?

Scales HD ships an update every 95 months, and Architects Ruler every 3 months. Most recently, Scales HD was updated on November 1, 2026 and Architects Ruler on November 5, 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.*