System Designer vs myTextViewer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
System Designer
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.
- UML-based system modeling
- Code skeleton generation
- Graphical component creation
- MSON format for model definition
- Dynamic type checking
- Cross-device synchronization via GitHub
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System Designer is a low-code development platform for creating systems. No matter the frameworks you use and the code you write, the most important is the model that you define to create your system. System Designer helps you to design this model and to generate the classes and components to build your system. DESIGN YOUR SYSTEM WITH EASE If you look at the different JavaScript frameworks on the market, you will notice that they all have their own way to define a model, generally only with code. System Designer uses UML, a standard, to define your model. So you probably already know how to design in System Designer even if you have never run it. The definition of the model is stored on a JSON format called MSON. With MSON you can define types, classes, one to one / one to many relationships and multi inheritance between classes. CODE THE BEHAVIOR OF YOUR SYSTEM Once you have created your model, System Designer generates the skeletons of all your methods. You only have then to add your code to implement them. System Designer provides you helpers to manage your components. You can easily navigate threw your components to create your application. CREATE COMPONENTS GRAPHICALLY There is no need to code to instantiate a component. Create a component in System Designer is like creating a document in a NoSQL Database. In fact, System Designer acts as an ODM (Object-Document Mapper) to manage your components as NoSQL Documents. RUN YOUR SYSTEM You can run your system directly from System Designer. Because you have defined a model for your application, a Dynamic Type Check is done on every action of your system. All warnings are send and shown in System Designer. DESIGN ON THE GO System Designer can be used on macOS, iPad or any browsers. System Designer has a Github module to synchronize your work between all these apps. You can begin your design on your Mac and then continue it on your iPad.
myTextViewer
Instantly open and view any text, code, or log file. This app offers professional syntax highlighting and line numbers, making it ideal for professionals who need to access and read various file formats on the go. It supports numerous common file types and provides customizable viewing themes.
- Open any text, code, or log file
- Syntax highlighting for common formats
- Line numbers display
- Light and dark viewing themes
- Share option integration
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Open any text, code, or log file instantly. myTextViewer provides professional syntax highlighting and line numbers for professionals on the go. Did you recently get an email with a text file that you could not open? Was it because the format of the file doesn't fit any app that you have installed? Search no more - myTextViewer allows you to open any of these files in a text viewer. Simple, fast, easy, as 1 2 3! Just: 1. Click on a file (from the downloads/Files app) or an attachment (from email apps) 2. Using the Share option, select myTextViewer as the target app. 3. View your file Even better - It can color most common files/source code formats (python, c#, yaml, json, and much more!), so even if the default viewer can show you the text, you'll still get much more from opening files with myTextViewer. Also included: ・Light/Dark text viewing themes ・Show/Hide line numbers Enjoy!
Screenshots
Verdict
The clearest difference is rating: System Designer at 4.4 against myTextViewer's 3.7. System Designer also leads on update cadence (monthly vs every 12 months) and review sentiment (78% vs 54%). myTextViewer's advantage is ratings volume (156 vs 17). On price, ads, in-app purchases and monetization model there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
System Designer holds the better App Store score, 4.4 against 3.7. That said, the two scores are not equally well evidenced: myTextViewer has 156 ratings behind it against 17, so its average is the more settled of the two. Written reviews point the same way: 78% of System Designer's written reviews are positive against 54% of myTextViewer's.
System Designer ships an update monthly, myTextViewer every 12 months. The most recent releases landed on September 18, 2026 and September 9, 2026 respectively.
| Parameter | System Designer | myTextViewer |
|---|---|---|
| Price | Free | Free |
| Rating | 4.4 (17 ratings) — better | 3.7 (156 ratings) |
| Positive reviews | 77.8% of reviews — better | 54.0% of reviews |
| Number of ratings | 17 | 156 — better |
| Update frequency | Monthly — better | Every 12 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.6 | 15.6 |
| Further details — not scored | ||
| Size | 7 MB | 6 MB |
| Age rating | 4+ | 4+ |
| Developer | Erwan Carriou | Yaniv Kalsky |
Customer experience
System Designer
myTextViewer
Bugs and requests
System Designer
Not enough reviews yet to summarise bugs or requests.
myTextViewer
Reported bugs
8 issues- App fails to open files from Files app
- JSON files display blank
- XML files not rendering properly
- App crashes or won't launch
- Incompatibility with iOS 14 and iOS 16
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- Text files cannot be opened
- Help screen appears instead of file content
- No response when sharing files to app
Requested features
7 requests- Search/find function within documents
- File editing capabilities
- Remove ads or ad-free option
- Support for action extensions
- Better file import options
Show 2 moreShow fewer
- Plain English display instead of code format
- Export functionality
In-app purchases
System Designer
No in-app purchases
myTextViewer
No in-app purchases









