Comparison

System Designer vs Diagrams Notepad 3

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

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.

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
Read full description

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.

About

Diagrams Notepad 3

Create and sync diagrams, flowcharts, and mind maps across iPhone, iPad, and Mac. Supports Apple Pencil for drawing and offers collaboration features. Export in various formats.

Highlights
  • Cross-device sync via iCloud
  • Vector-based shapes and connectors
  • Apple Pencil support
  • Diagram sharing and collaboration
  • Export to PDF, PNG, JPEG
  • Unlimited diagram size
Features
Read full description

NEW - Create diagrams on iPhone, iPad and Mac and sync them together! New Design - Pencil Support - Folders - File Export/Import - Markup Editing - UML Class Editor and more... Create quickly and creatively wonderful diagrams and notes, flowcharts, mind maps, pinboards, organigrams, software models and AWS diagrams on your iPhone, iPad and Mac. Sync your diagrams optionally and automatically between all iOS and macOS devices. Add shapes, connectors, images, drawings and weblinks. Draw shapes and connectors, take notes and add markup with Apple Pencil or a finger. Share diagrams and collaborate on them with other users through iCloud. Key features • Automatic sync using iCloud between your iOS and macOS devices • Vector based shapes and connectors • Color themes and styles for the entire diagram • Drag and drop (on iPad) or copy and paste to insert graphics, photos or URLs (rich links) from other apps directly to the diagram • Drawing shapes and connectors with Apple Pencil or a finger • Undo and redo all changes • Export diagrams as vector PDF documents or PNG or JPEG images • Diagram iCloud sharing and collaboration with your team or friends • Designed for iOS and iCloud The app uses iCloud to optionally and automatically sync diagrams between your iOS and macOS devices. You can also share your diagrams and collaborate on them with other users. • Diagrams without size limits The diagram automatically resizes to fit your content as you add more shapes. You can add shapes from any side of the diagram. • Each diagram has its own style Your recently used color styles, shapes and connectors will be saved separately for each diagram. • Replace shapes and connectors at any time Replace any selected shapes in the diagram with another shape from the toolbar or with an image or web-link from the clipboard. The existing text and connections of connectors will not change. • Free version with all functions Download the free version of the application and try out all the features. You can add and edit two diagrams with a limited number of shapes in each diagram. Upgrading to an unlimited number of diagrams and shapes is possible through an In-App Purchase. • We are looking forward to your feedback If you enjoy using the Diagrams Notepad app, please add a rating or write a review on the App Store. If you have further questions or suggestions about the app, please send us an e-mail to: info@diagrams-notepad.com Thank you for using the Diagrams Notepad app!

Screenshots

System Designer3 screens
Diagrams Notepad 34 screens

Verdict

The call

The clearest difference is rating: System Designer at 4.4 against Diagrams Notepad 3's 3.5. System Designer also leads on review sentiment (78% vs 39%) and in-app purchases (none vs 1). Diagrams Notepad 3's advantage is ratings volume (51 vs 17). On price, update cadence, ads and device support 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Diagrams Notepad 3 sells 1 one-off in-app purchase. System Designer asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

System Designer holds the better App Store score, 4.4 against 3.5. Both are backed by a comparable volume of ratings — 17 and 51 respectively. Written reviews point the same way: 78% of System Designer's written reviews are positive against 39% of Diagrams Notepad 3's.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly monthly. The most recent releases landed on September 18, 2026 and June 9, 2026 respectively.

Scorecard5 real differences · 5 level
System Designer versus Diagrams Notepad 3: the parameters behind the verdict, then further details
ParameterSystem DesignerDiagrams Notepad 3
PriceFreeFree
Rating4.4 (17 ratings) — better3.5 (51 ratings)
Positive reviews77.8% of reviews — better39.0% of reviews
Number of ratings1751 — better
Update frequencyMonthlyMonthly
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac — better
Requires iOS15.615.0 — better
Further details — not scored
Size7 MB29 MB
Age rating4+4+
DeveloperErwan Carriousunata UG (haftungsbeschraenkt)

Customer experience

System Designer

All ratings17 ratings
Positive88.2%
Neutral0.0%
Negative11.8%
Written reviews9 reviews
Positive77.8%
Neutral0.0%
Negative22.2%

Diagrams Notepad 3

All ratings51 ratings
Positive62.7%
Neutral3.9%
Negative33.3%
Written reviews105 reviews
Positive39.0%
Neutral8.6%
Negative52.4%

In-app purchases

None

System Designer

No in-app purchases

1 purchases

Diagrams Notepad 3

One-time1
  • Unlimited number of diagrams$22.99

Questions

Is System Designer free?
System Designer is free to download, with no in-app purchases.
Is Diagrams Notepad 3 free?
Diagrams Notepad 3 is free to download, with in-app purchases available.
Which has better reviews, System Designer or Diagrams Notepad 3?
System Designer is rated higher. System Designer averages 4.4 out of 5 from 17 ratings, while Diagrams Notepad 3 averages 3.5 from 51 ratings.
Do System Designer or Diagrams Notepad 3 have ads?
Neither System Designer nor Diagrams Notepad 3 shows ads.
Which is updated more often, System Designer or Diagrams Notepad 3?
System Designer ships an update monthly, and Diagrams Notepad 3 monthly. Most recently, System Designer was updated on September 18, 2026 and Diagrams Notepad 3 on June 9, 2026.

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