# STEP Viewer vs STP One

The clearest difference is in-app purchases: STEP Viewer at none against STP One's 2. STEP Viewer also leads on iOS requirement (13.0 vs 16.4). STP One's advantage is update cadence (every 3 days vs every 5 days). On price, ads and device support there is nothing between them.

Both are free to download. STP One sells 2 in-app purchases, starting at $9.99 per month. STEP Viewer asks for nothing beyond the download.

STEP Viewer ships an update every 5 days, STP One every 3 days. The most recent releases landed on October 24, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | STEP Viewer | STP One |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/step-viewer/id6756539299/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 5 days | **Every 3 days** |
| Size | 61 MB | 13 MB |
| Requires iOS | **13.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Smart Cube Labs Co., Ltd.](https://appshunter.io/developer/1456342688) | [JAEYUN HWANG](https://appshunter.io/developer/6799562363) |

## What reviewers say

### STEP Viewer

[App page](https://appshunter.io/ios/app/step-viewer/id6756539299)

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

**In-app purchases:** none


### STP One

[App page](https://appshunter.io/ios/app/stp-one-step-cad-viewer/id6802912144)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 스텝원 Pro 월간 | $9.99 | per month |
| 스텝원 Pro 연간 | $69.99 | per year |


## Frequently asked questions

### Is STEP Viewer free?

STEP Viewer is free to download, with no in-app purchases.

### Is STP One free?

STP One is free to download, with in-app purchases available.

### Do STEP Viewer or STP One have ads?

Neither STEP Viewer nor STP One shows ads.

### Which is updated more often, STEP Viewer or STP One?

STEP Viewer ships an update every 5 days, and STP One every 3 days. Most recently, STEP Viewer was updated on October 24, 2026 and STP One on October 10, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*