# Span Calc vs RedX Decks

The clearest difference is rating: RedX Decks at 4.3 against Span Calc's 2.9. RedX Decks also leads on ratings volume (528 vs 15). Span Calc's advantage is in-app purchases (none vs 10). On price, review sentiment, update cadence and ads there is nothing between them.

Both are free to download. RedX Decks sells 9 in-app purchases, starting at $6.99 per month. Span Calc asks for nothing beyond the download.

RedX Decks holds the better App Store score, 4.3 against 2.9. That said, the two scores are not equally well evidenced: RedX Decks has 528 ratings behind it against 15, so its average is the more settled of the two. Written reviews point the same way: 30% of Span Calc's written reviews are positive against 31% of RedX Decks's.

Both ship on a similar rhythm, roughly every 10 days. The most recent releases landed on October 12, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Span Calc | RedX Decks |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.9 (15 ratings)](https://appshunter.io/ios/app/span-calc/id380481343/reviews) | **[4.3 (528 ratings)](https://appshunter.io/ios/app/redx-decks-3d-deck-builder/id6474487367/reviews)** |
| Number of ratings | 15 | **528** |
| Positive reviews | 29.6% of reviews | **30.8% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 10 days | Every 10 days |
| Monetization | **Free** | Free with in-app purchases |
| Size | 168 MB | 177 MB |
| Requires iOS | **14.2** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 17+ | 4+ |
| Developer | [American Wood Council](https://appshunter.io/developer/380481346) | [RedX Technology Inc](https://appshunter.io/developer/835492291) |

## What reviewers say

### Span Calc

[App page](https://appshunter.io/ios/app/span-calc/id380481343)

Calculate maximum horizontal spans for wood joists and rafters using various lumber species and grades. Compares multiple options for common loading conditions based on NDS® standards.

**Highlights:** Calculates joist and rafter spans, Supports all softwood and hardwood lumber, Uses 2021 NDS® for Wood Construction, Compares multiple species and grades, Handles common loading conditions

**Features:** macOS Compatibility

**In-app purchases:** none


### RedX Decks

[App page](https://appshunter.io/ios/app/redx-decks-3d-deck-builder/id6474487367)

Design and visualize complex deck structures, including roofs and stairs, with automatic framing and structural calculations. Generate professional, permit-ready blueprints and detailed material lists for efficient construction.

**Highlights:** 3D deck and roof design, Automatic framing layouts, Structural calculations, Permit-ready blueprints, Material and cut lists, 3D visualization and renders

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

**In-app purchases (9)**

| Purchase | Price | Billing |
| --- | --- | --- |
| RedX Decks Pro | $6.99 | per month |
| RedX Apps Pro++ Monthly | $9.99 | per month |
| RedX Apps Pro++ | $59.99 | per year |
| RedX Decks Pro | $89.99 | per year |
| RedX Decks Pro | $119.99 | per year |
| RedX Apps Bundle | $179.99 | per year |
| 20 Render Credits | $9.99 | one-time |
| 100 Render Credits | $29.99 | one-time |
| 200 Render Credits | $44.99 | one-time |


## Frequently asked questions

### Is Span Calc free?

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

### Is RedX Decks free?

RedX Decks is free to download, with in-app purchases available.

### Which has better reviews, Span Calc or RedX Decks?

RedX Decks is rated higher. Span Calc averages 2.9 out of 5 from 15 ratings, while RedX Decks averages 4.3 from 528 ratings.

### Do Span Calc or RedX Decks have ads?

Neither Span Calc nor RedX Decks shows ads.

### Which is updated more often, Span Calc or RedX Decks?

Span Calc ships an update every 10 days, and RedX Decks every 10 days. Most recently, Span Calc was updated on October 12, 2026 and RedX Decks on October 14, 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.*