# Technology Readiness Levels vs System Designer

The clearest difference is rating: Technology Readiness Levels at 5.0 against System Designer's 4.4. System Designer's advantage is update cadence (monthly vs every 8 months) and ratings volume (17 vs 2). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Technology Readiness Levels holds the better App Store score, 5.0 against 4.4. That said, the two scores are not equally well evidenced: System Designer has 17 ratings behind it against 2, so its average is the more settled of the two.

Technology Readiness Levels ships an update every 8 months, System Designer monthly. The most recent releases landed on June 1, 2026 and September 18, 2026 respectively.

## The numbers

| Metric | Technology Readiness Levels | System Designer |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/technology-readiness-levels/id644843941/reviews)** | [4.4 (17 ratings)](https://appshunter.io/ios/app/system-designer/id1132983280/reviews) |
| Number of ratings | 2 | **17** |
| Positive reviews | — | 77.8% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 8 months | **Monthly** |
| Monetization | Free | Free |
| Size | 1 MB | 7 MB |
| Requires iOS | 26.0 | **15.6** |
| Devices | iPhone | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Russell Shannon](https://appshunter.io/developer/505317310) | [Erwan Carriou](https://appshunter.io/developer/1102494853) |

## What reviewers say

### Technology Readiness Levels

[App page](https://appshunter.io/ios/app/technology-readiness-levels/id644843941)

Quickly access definitions and descriptions for Department of Defense and NASA Technology Readiness Levels (TRLs). Understand the distinctions between different TRL stages and their supporting information.

**Highlights:** DoD and NASA TRL definitions, Detailed descriptions for each TRL, Supporting information (DoD), SETR Process alignment (DoD), Quick reference guide

**In-app purchases:** none


### System Designer

[App page](https://appshunter.io/ios/app/system-designer/id1132983280)

Design complex systems using a low-code platform that leverages UML standards. Generate code skeletons and manage components graphically. Run and test your system with dynamic type checking.

**Highlights:** UML-based system modeling, Code skeleton generation, Graphical component creation, MSON format for model definition, Dynamic type checking, Cross-device synchronization via GitHub

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Technology Readiness Levels free?

Technology Readiness Levels is free to download, with no in-app purchases.

### Is System Designer free?

System Designer is free to download, with no in-app purchases.

### Which has better reviews, Technology Readiness Levels or System Designer?

Technology Readiness Levels is rated higher. Technology Readiness Levels averages 5.0 out of 5 from 2 ratings, while System Designer averages 4.4 from 17 ratings.

### Do Technology Readiness Levels or System Designer have ads?

Neither Technology Readiness Levels nor System Designer shows ads.

### Which is updated more often, Technology Readiness Levels or System Designer?

Technology Readiness Levels ships an update every 8 months, and System Designer monthly. Most recently, Technology Readiness Levels was updated on June 1, 2026 and System Designer on September 18, 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.*