# Seals Catalog vs STL Simple Viewer

The clearest difference is rating: Seals Catalog at 5.0 against STL Simple Viewer's 4.3. Seals Catalog also leads on in-app purchases (none vs 4) and ads (none vs shown). STL Simple Viewer's advantage is ratings volume (909 vs 1). On price, update cadence and device support there is nothing between them.

Both are free to download. STL Simple Viewer sells 4 in-app purchases, starting at $0.99 per 7 days. Seals Catalog asks for nothing beyond the download.

Seals Catalog holds the better App Store score, 5.0 against 4.3. That said, the two scores are not equally well evidenced: STL Simple Viewer has 909 ratings behind it against 1, so its average is the more settled of the two.

Seals Catalog ships an update every 10 months, STL Simple Viewer every 5 months. The most recent releases landed on September 30, 2026 and October 19, 2026 respectively.

## The numbers

| Metric | Seals Catalog | STL Simple Viewer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/seals-catalog/id1460114822/reviews)** | [4.3 (909 ratings)](https://appshunter.io/ios/app/stl-simple-viewer/id1493598400/reviews) |
| Number of ratings | 1 | **909** |
| Positive reviews | — | 18.1% of reviews |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 10 months | **Every 5 months** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 34 MB | 19 MB |
| Requires iOS | **9.0** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Trelleborg Sealing Solutions](https://appshunter.io/developer/396863758) | [Victor Bovio](https://appshunter.io/developer/327627515) |

## What reviewers say

### Seals Catalog

[App page](https://appshunter.io/ios/app/seals-catalog/id1460114822)

Access detailed product information, material data sheets, and compare multiple seals. Filter products by item number, type, or operating conditions to find specific items. Request quotations directly through the app by adding items to a shopping cart.

**Highlights:** Detailed product descriptions, Material data sheets, Seal comparison tool, Product search and filtering, Request quotation, Shopping cart functionality

**Features:** macOS Compatibility

**In-app purchases:** none


### STL Simple Viewer

[App page](https://appshunter.io/ios/app/stl-simple-viewer/id1493598400)

Easily view and interact with 3D STL CAD models. Supports various file types and offers advanced rendering options for detailed analysis. Get model information and explore interiors with clipping planes.

**Highlights:** View ASCII and Binary STL files, Load STL from ZIP, Rotate, pan, and zoom, Orthogonal and Perspective modes, Model info (triangle count, bounding box), Rendering options (faces, edges, transparency), Clipping plane for interiors

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

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro version (1 week plan) | $0.99 | per 7 days |
| Pro version (1 month plan) | $1.99 | per month |
| Remove Ads | $2.99 | one-time |
| Export Pack | $3.99 | one-time |

**What reviewers like**

- 🚀 Simple and intuitive viewer
- 👍 Useful viewing options
- 💡 Supports multiple file formats

**What reviewers complain about**

- 🐛 Frequent crashes
- 🔋 High battery consumption
- 🚨 Excessive and intrusive ads
- 🔍 Limited functionality for larger files

**Reported bugs**

- App crashes when opening larger STL files
- Inability to open some file formats
- Ads continue to appear even after paying for ad removal

**Requested features**

- Add ability to save color/lighting settings
- Improve stability and reduce crashes
- Provide an ad-free paid version


## Frequently asked questions

### Is Seals Catalog free?

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

### Is STL Simple Viewer free?

STL Simple Viewer is free to download, with in-app purchases available.

### Which has better reviews, Seals Catalog or STL Simple Viewer?

Seals Catalog is rated higher. Seals Catalog averages 5.0 out of 5 from 1 ratings, while STL Simple Viewer averages 4.3 from 909 ratings.

### Do Seals Catalog or STL Simple Viewer have ads?

STL Simple Viewer shows ads; Seals Catalog does not.

### Which is updated more often, Seals Catalog or STL Simple Viewer?

Seals Catalog ships an update every 10 months, and STL Simple Viewer every 5 months. Most recently, Seals Catalog was updated on September 30, 2026 and STL Simple Viewer on October 19, 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.*