# RST Scope Pro vs Open Authenticator by Skyost

The clearest difference is price: Open Authenticator by Skyost at Free against RST Scope Pro's $1.99. Open Authenticator by Skyost also leads on device support (4 vs 2). RST Scope Pro's advantage is in-app purchases (none vs 2) and update cadence (every 6 days vs fortnightly). On ads and iOS requirement there is nothing between them.

Open Authenticator by Skyost is free to download; RST Scope Pro costs $1.99 up front. Open Authenticator by Skyost sells 2 in-app purchases, starting at $0.99 per month. RST Scope Pro asks for nothing beyond the download.

RST Scope Pro ships an update every 6 days, Open Authenticator by Skyost fortnightly. The most recent releases landed on October 18, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | RST Scope Pro | Open Authenticator by Skyost |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | — | **[4.4 (9 ratings)](https://appshunter.io/ios/app/open-authenticator-by-skyost/id6479272927/reviews)** |
| Number of ratings | — | **9** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 6 days** | Fortnightly |
| Monetization | — | Free with in-app purchases |
| Size | 1 MB | 56 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod, Mac** |
| Age rating | 4+ | 4+ |
| Developer | [koji kamogawa](https://appshunter.io/developer/1488210713) | [Hugo Delaunay](https://appshunter.io/developer/1456648264) |

## What reviewers say

### RST Scope Pro

[App page](https://appshunter.io/ios/app/rst-scope-pro/id1550939327)

**In-app purchases:** none


### Open Authenticator by Skyost

[App page](https://appshunter.io/ios/app/open-authenticator-by-skyost/id6479272927)

This app generates Time-Based One-Time Passwords (TOTPs) to enhance online account security through two-factor authentication. It offers cross-platform syncing, a self-hostable backend, and an intuitive interface for managing your security codes.

**Highlights:** Generates Time-Based One-Time Passwords (TOTPs), Enhances online account security with 2FA, Cross-platform token syncing, Self-hostable backend option, Fast and easy-to-use interface, Open-source and free for local use

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Contributor Plan: Monthly | $0.99 | per month |
| Contributor Plan: Annual | $9.99 | per year |


## Frequently asked questions

### Is RST Scope Pro free?

RST Scope Pro costs $1.99, with no in-app purchases.

### Is Open Authenticator by Skyost free?

Open Authenticator by Skyost is free to download, with in-app purchases available.

### Do RST Scope Pro or Open Authenticator by Skyost have ads?

Neither RST Scope Pro nor Open Authenticator by Skyost shows ads.

### Which is updated more often, RST Scope Pro or Open Authenticator by Skyost?

RST Scope Pro ships an update every 6 days, and Open Authenticator by Skyost fortnightly. Most recently, RST Scope Pro was updated on October 18, 2026 and Open Authenticator by Skyost on October 14, 2026.

---

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