# System Designer — Design First. Then Code. > Low-code platform for designing systems and generating code skeletons. (iPhone/iPad app by Erwan Carriou.) - Source: https://appshunter.io/ios/app/system-designer/id1132983280 (this page in markdown: same URL + `.md`) - Developer: [Erwan Carriou](https://appshunter.io/developer/1102494853) - Category: Productivity - Price: Free - Rating: 4.40/5 from 17 App Store ratings · 9 written reviews indexed - Age rating: 4+ - Requires: iOS 15.6 · 7 MB - Languages: American English - Released: 2016-07-29 - Data updated: 2026-06-10 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/system-designer/id1132983280/reviews.md ## What is System Designer? 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. ## Key features - UML-based system modeling - Code skeleton generation - Graphical component creation - MSON format for model definition - Dynamic type checking - Cross-device synchronization via GitHub ## Recent user reviews (9 of 9) All indexed reviews: https://appshunter.io/ios/app/system-designer/id1132983280/reviews.md ### 5/5 — Awesome App *2022-05-14* Love the app. Using it to help me plan my models for a Django app and api! Please keep innovating and working on this! **Developer response:** Thank you for your review and support :) ! ### 1/5 — Glorified web app *2019-04-06* The whole app runs only in landscape and uses quirky web-based UI. **Developer response:** Thank you for your feedback. You can use System Designer now in portait and landscape modes. Moreover, as said in the description, System Designer is a web app, a Progressive Web App (PWA) to be more precise, so it has all the features of a native app (offline mode, ...). System Designer is free and open source, so you can create an issue on the GitHub repository to ask more questions about that. ### 4/5 — Complex and feature filled... A little overwhelming to start with. *2019-02-13* This app promises to be an IDE for your project design, and it definitely delivers on that promise. You’ll need to familiarise yourself with the workflow on the (linked but external, inapp would have been nice) getting started guide and play with it a little but you can definitely get a lot done if you invest the time overcoming the initial hurdle. My main gripe is that it’s extremely tedious to map out models manually using JS using touch input and that there’s no way to quickly throw together simple graphs if you’re just sketching out an idea in your head. Great app though, thanks! **Developer response:** Thank you for your review and your feedback! I will check how I can ease the system process creation (as I see it, I will expose a simple mode (i.e. pure UI) and an advanced mode (i.e. full access to the MSON file) for system creation). ### 5/5 — Great work! *2019-01-18* I honestly thought this was one of those "too good to be true" apps but boy was I wrong. Such a great app, I also highly recommend the MacOSX version. Developer you are awesome! **Developer response:** Thank you for the review! ### 5/5 — . *2018-12-01* Thank you for this great app and for sharing it for free. **Developer response:** You're welcome and thanks for the review. ### 2/5 — Not what expected *2018-12-01* Well designed, looks good. I think it’s too explicit and tied in to a certain way of working. I think it’d be much more beneficial if it wasn’t tied to a language like javascript or tied to a specific way of working. Not really useable for me. **Developer response:** Thank you for your feedback. In fact, it possible to extend System Designer to other languages (system description is agnostic), but you will loose some great features that we have with JavaScript (like the code generation in memory). Moreover, if you think you have too much contraints with System Designer, you can try create systems with System Runtime, the JavaScript library on which is based System Designer. ### 4/5 — Useful for API Design *2018-11-16* Using this with JSON Designer to design an api. 2 stars for usefulness. 2 stars for stability (haven’t had any crashes yet). .5 stars for design, could use some polish for the ui. Feels a bit bulky as well. **Developer response:** Thank you for your feedback. It would be useful for me if you can create an issue on the GitHub repository of the app in order to know where I can improve the UI. ### 5/5 — Great job *2018-06-25* Why you make the big greating for free, I don’t know, but any way thank you. I used to learn and work. **Developer response:** Thank you for the review. Nice to know that the app is helping you on your work. ### 5/5 — Amazing *2017-10-21* Please make iPhone have extensions support please ## Frequently asked questions about System Designer ### What is System Designer used for? System Designer is a low-code development platform that helps users design systems using UML standards. It then generates code skeletons and allows for graphical component creation and system execution with dynamic type checking. ### How does System Designer handle system modeling? System Designer uses UML, a standard modeling language, to define system models. These models are stored in MSON format, allowing for the definition of types, classes, relationships, and multi-inheritance. ### Can I run my system directly from System Designer? Yes, you can run your system directly from System Designer. The platform performs dynamic type checking on every action, sending any warnings to the System Designer interface. ### What platforms is System Designer available on? System Designer is available on macOS, iPad, and in any web browser, making it accessible for design on the go. It also features a GitHub module for synchronizing work across these platforms. ### How does System Designer manage components? System Designer acts as an ODM (Object-Document Mapper), managing your components as NoSQL Documents. This allows for easy navigation and creation of application components without needing to code. ### Is System Designer free to use? Yes, System Designer is available for free. It does not have any in-app purchases or advertisements, offering a completely free experience for users. ### How often is System Designer updated? System Designer was last updated on January 28, 2024, with version 5.4.0. This indicates a relatively active development cycle, suggesting regular improvements and bug fixes. ### What is the user sentiment for System Designer? System Designer has a strong user rating of 4.4 stars from 17 ratings, indicating generally positive user sentiment. Users appreciate its capabilities in system design and code generation. ## Version history (last 5 releases) ### 5.4.0 — 2024-01-28 - Fixed: some minor UX issues. - Improved: performance and stability. ### 5.3.1 — 2024-01-21 - Updated: logo icon. - Improved: performance and stability. ### 5.3.0 — 2024-01-15 - Improved: performance and stability. ### 5.1.1 — 2022-01-03 - Improved: performance and stability ### 5.1.0 — 2022-01-03 - Improved: performance and stability ## Apps similar to System Designer | App | Rating | Price | Category | | --- | --- | --- | --- | | [PlantUML App](https://appshunter.io/ios/app/plantuml-app/id6444164984) | 3.0 (4) | $0.99 | Productivity | | [Flowdia Diagrams](https://appshunter.io/ios/app/flowdia-diagrams/id1170864140) | 3.5 (65) | Free | Productivity | | [CodeBrew - IDE for Java](https://appshunter.io/ios/app/codebrew-ide-for-java/id6475267297) | 3.8 (9) | Free | Productivity | | [ExcalidrawZ](https://appshunter.io/ios/app/excalidrawz/id6636493997) | 4.3 (7) | Free | Productivity | | [Apollon - UML Modeling Editor](https://appshunter.io/ios/app/apollon-uml-modeling-editor/id6474762031) | — | Free | Productivity | | [Lekh: whiteboard & diagramming](https://appshunter.io/ios/app/lekh-whiteboard-and-diagramming/id576124115) | 4.0 (12) | Free | Productivity | ## Related topics [erwan carriou](https://appshunter.io/ios/topics/erwan-carriou) · [system designer](https://appshunter.io/ios/topics/system-designer) · [system design](https://appshunter.io/ios/topics/system-design) · [uml](https://appshunter.io/ios/topics/uml) · [system](https://appshunter.io/ios/topics/system) · [system design corp](https://appshunter.io/ios/topics/system-design-corp) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*