# STL File Viewer Pro vs STEP File Viewer

The clearest difference is review sentiment: STEP File Viewer at 63% against STL File Viewer Pro's 10%. STEP File Viewer also leads on ads (none vs shown). STL File Viewer Pro's advantage is rating (4.5 vs 3.2) and ratings volume (81 vs 6). On price, update cadence, in-app purchases and monetization model there is nothing between them.

Both are free to download. STL File Viewer Pro sells 3 in-app purchases, starting at $1.99 per 7 days and STEP File Viewer sells 12 in-app purchases, starting at $1.99 per 7 days. Whichever you choose, the download price is not the number that matters.

STL File Viewer Pro holds the better App Store score, 4.5 against 3.2. That said, the two scores are not equally well evidenced: STL File Viewer Pro has 81 ratings behind it against 6, so its average is the more settled of the two. Written reviews complicate that: 10% of STL File Viewer Pro's written reviews are positive against 63% of STEP File Viewer's, so the app with the better star average is not the one people write more warmly about.

Both ship on a similar rhythm, roughly fortnightly. The most recent releases landed on October 25, 2026 and October 26, 2026 respectively.

## The numbers

| Metric | STL File Viewer Pro | STEP File Viewer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.5 (81 ratings)](https://appshunter.io/ios/app/stl-file-viewer-pro/id6741022143/reviews)** | [3.2 (6 ratings)](https://appshunter.io/ios/app/step-file-viewer/id6755721056/reviews) |
| Number of ratings | **81** | 6 |
| Positive reviews | 10.0% of reviews | **62.5% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | Yes | **No** |
| Update frequency | Fortnightly | Fortnightly |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Best chart rank | **#55** | #200 |
| Size | 16 MB | 33 MB |
| Requires iOS | 16.6 | **16.0** |
| Devices | iPhone, iPad | **iPhone, iPad, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [Andeesh Mehdi Syed](https://appshunter.io/developer/1676226599) | [维 艾](https://appshunter.io/developer/1771300149) |

## What reviewers say

### STL File Viewer Pro

[App page](https://appshunter.io/ios/app/stl-file-viewer-pro/id6741022143)

**Currently charting:** #55 Top Grossing · Developer Tools, #174 Top Free · Developer Tools (US App Store)

Easily view, rotate, and inspect 3D STL files on your iPhone or iPad. Load models instantly from various sources for 3D printing, design review, or engineering inspection.

**Highlights:** Instant STL file loading, Full 360° rotation and zoom, Sharp detail rendering, Light and dark mode support, Lightweight and fast performance, Open files from Files, email, AirDrop

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly | $1.99 | per 7 days |
| Monthly | $3.99 | per month |
| Ad Free for 1 Year | $24.99 | per year |


### STEP File Viewer

[App page](https://appshunter.io/ios/app/step-file-viewer/id6755721056)

**Currently charting:** #200 Top Free · Developer Tools (US App Store)

View and interact with 3D CAD files like STEP and IGES. Inspect internal geometry, measure dimensions, and export models in various formats. Ideal for engineers, designers, and students needing to visualize complex designs without expensive software.

**Highlights:** 3D model viewing with pan, zoom, and rotate, Solid, shaded, and wireframe display modes, Measure dimensions and features, Section planes for internal geometry inspection, Export models to STL, OBJ, glTF, and more, Supports assembly data and PMI annotations

**Features:** Family Sharing, Vision Pro support

**In-app purchases (12)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Flex | $1.99 | per 7 days |
| Pro Light | $4.99 | per month |
| Pro Infinity | $19.99 | per year |
| Export as USDZ | $1.99 | one-time |
| Export as PNG | $2.99 | one-time |
| Export as OBJ | $3.99 | one-time |
| Export as STL | $3.99 | one-time |
| IGES/STEP Model Import | $3.99 | one-time |
| Projection view generation & export | $4.99 | one-time |
| Cross Section View | $4.99 | one-time |
| Exploded View | $4.99 | one-time |
| Export all formats | $15.99 | one-time |


## Frequently asked questions

### Is STL File Viewer Pro free?

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

### Is STEP File Viewer free?

STEP File Viewer is free to download, with in-app purchases available.

### Which has better reviews, STL File Viewer Pro or STEP File Viewer?

STL File Viewer Pro is rated higher. STL File Viewer Pro averages 4.5 out of 5 from 81 ratings, while STEP File Viewer averages 3.2 from 6 ratings.

### Do STL File Viewer Pro or STEP File Viewer have ads?

STL File Viewer Pro shows ads; STEP File Viewer does not.

### Which is updated more often, STL File Viewer Pro or STEP File Viewer?

STL File Viewer Pro ships an update fortnightly, and STEP File Viewer fortnightly. Most recently, STL File Viewer Pro was updated on October 25, 2026 and STEP File Viewer on October 26, 2026.

### Which is more popular, STL File Viewer Pro or STEP File Viewer?

STL File Viewer Pro currently peaks at #55 in the App Store charts, and STEP File Viewer at #200. Chart position reflects recent download velocity rather than total install base.

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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.*