Mac Sequence Diagram makes it incredibly easy to create UML 2.0 style sequence diagrams, using nothing more than plain text (and a sprinkling of emoji).

It supports :-

• Participants
• Signals
• Nested Interaction Frames
• Nested Activation Boxes
• Found signals
• Lost signals
• Multiple signal arrow line styles
• Multiple signal arrow head styles
• Export PDF
• Export PNG
• Export SVG
• Syntax Highlighting in Diagram Text Editor
• Error highlighting
• Canvas zoom up to 14x
• Collapsable Diagram Editor
• Light & Dark modes
• Keyword Auto-Completion
• Participant name Auto-Completion
• Version Control Friendly File Format

And so much more.

Feedback, issues and suggestions are welcomed.


What's New

Version 1.5.15

* Fixes an issue where participant aliases could not start with “as”

Other recent enhancements
* Adds the ability for notes to span multiple participants (note over a,b)
* Adds support for object destruction using the “destroy” keyword
* Adds support for Mermaid syntax object lifeline activation/deactivation (+/-)
* Improves context awareness of auto-completion suggestions
* Adds automatic indentation preservation
* You can now toggle the insertion/removal of comments over multiple lines
* You can add/remove indentation to multiple-lines at once

A massive thank-you for all the feedback and suggestions.

Please keep them coming and don’t forget to rate and/or review.

Thanks again for your valued support.

-- Mike

Ratings and Reviews

5.0 out of 5
14 Ratings
14 Ratings

Easy to use app

Spartan Slasher

Needed to create some sequence diagrams quickly, this app was perfect, tried to use a dev environment before hand, cumbersome and slow to get running with plugins. This app worked a treat for what i needed. Would love to have a larger font options output for Jpegs and PDFs though, but otherwise spot on.

Powerful and easy to use


I was frustrated trying to make sequence diagrams with other tools on the market, and wrestling with dragging lines around, but this app is perfect for me!
I can create diagrams using plain text, edit and share them with my team.

Developer Response

Hi Owen, Thank-you for the incredibly kind review. It is greatly appreciated. Please tell your friends an colleagues. 🤓



I love the fact one just describes a diagram and it's drawn for you.

The app's even better now a PDF or PNG of the diagram can be sent direct to the clipboard :)

Developer Response

Thank-you, Beerbacon. It's greatly appreciated. -- Mike


Mike O Abidakun
10.7 MB
Age Rating
Rated 4+
© Mike O. Abidakun


  • Family Sharing

    Up to six family members will be able to use this app with Family Sharing enabled.