# STEP File Viewer vs Reality Prep Preview

The clearest difference is in-app purchases: Reality Prep Preview at none against STEP File Viewer's 12. STEP File Viewer's advantage is update cadence (fortnightly vs every 6 weeks) and iOS requirement (16.0 vs 18.0). On price, ads and device support there is nothing between them.

Both are free to download. STEP File Viewer sells 12 in-app purchases, starting at $1.99 per 7 days. Reality Prep Preview asks for nothing beyond the download.

STEP File Viewer ships an update fortnightly, Reality Prep Preview every 6 weeks. The most recent releases landed on October 30, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | STEP File Viewer | Reality Prep Preview |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.2 (6 ratings)](https://appshunter.io/ios/app/step-file-viewer/id6755721056/reviews)** | — |
| Number of ratings | **6** | — |
| Positive reviews | 62.5% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 6 weeks |
| Monetization | Free with in-app purchases | — |
| Size | 33 MB | 5 MB |
| Requires iOS | **16.0** | 18.0 |
| Devices | iPhone, iPad, Mac | iPhone, iPad, Vision Pro |
| Age rating | 4+ | 4+ |
| Developer | [维 艾](https://appshunter.io/developer/1771300149) | [Victory Software (Pty) Ltd](https://appshunter.io/developer/1896498575) |

## What reviewers say

### STEP File Viewer

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

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 |


### Reality Prep Preview

[App page](https://appshunter.io/ios/app/reality-prep-preview/id6784059026)

**In-app purchases:** none


## Frequently asked questions

### Is STEP File Viewer free?

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

### Is Reality Prep Preview free?

Reality Prep Preview is free to download, with no in-app purchases.

### Do STEP File Viewer or Reality Prep Preview have ads?

Neither STEP File Viewer nor Reality Prep Preview shows ads.

### Which is updated more often, STEP File Viewer or Reality Prep Preview?

STEP File Viewer ships an update fortnightly, and Reality Prep Preview every 6 weeks. Most recently, STEP File Viewer was updated on October 30, 2026 and Reality Prep Preview on October 28, 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.*