# Reliability of systems vs Учебник Docker

The clearest difference is in-app purchases: Учебник Docker at none against Reliability of systems's 1. Учебник Docker also leads on update cadence (every 2 months vs every 18 months). Reliability of systems's advantage is iOS requirement (13.0 vs 15.6). On price, ads and device support there is nothing between them.

Both are free to download. Reliability of systems sells 1 one-off in-app purchase. Учебник Docker asks for nothing beyond the download.

Reliability of systems ships an update every 18 months, Учебник Docker every 2 months. The most recent releases landed on October 10, 2026 and October 20, 2026 respectively.

## The numbers

| Metric | Reliability of systems | Учебник Docker |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 18 months | **Every 2 months** |
| Size | 4 MB | 19 MB |
| Requires iOS | **13.0** | 15.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Siu Yuen Ho](https://appshunter.io/developer/814088527) | [Mikhail Shmarov](https://appshunter.io/developer/1715239557) |

## What reviewers say

### Reliability of systems

[App page](https://appshunter.io/ios/app/reliability-of-systems/id6443837301)

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock Pro feature | $1.99 | one-time |


### Учебник Docker

[App page](https://appshunter.io/ios/app/docker/id6742394168)

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

**In-app purchases:** none


## Frequently asked questions

### Is Reliability of systems free?

Reliability of systems is free to download, with in-app purchases available.

### Is Учебник Docker free?

Учебник Docker is free to download, with no in-app purchases.

### Do Reliability of systems or Учебник Docker have ads?

Neither Reliability of systems nor Учебник Docker shows ads.

### Which is updated more often, Reliability of systems or Учебник Docker?

Reliability of systems ships an update every 18 months, and Учебник Docker every 2 months. Most recently, Reliability of systems was updated on October 10, 2026 and Учебник Docker on October 20, 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.*