PrivyMermaid (iOS)
Private, Local-First Diagram Editor for iPhone & iPad
Overview
PrivyMermaid is a privacy-focused diagram editor for iPhone and iPad. Write, preview, theme, export, and organize Mermaid and D2 diagrams locally. A Diagram Cloud account and automatic sync are optional, while Pro adds configurable AI generation, chat, fixing, and refactoring.
Features
- Offline rendering — Instantly visualize Mermaid and D2 code into diagrams without an internet connection
- Live preview — See diagram changes in real-time as you edit the source
- Theme selection — Choose from Light, Dark, Forest, and Neutral Mermaid themes
- Multi-format export — Export diagrams as SVG, PNG, PDF, GIF, or source files (.mmd and .d2) via the iOS share sheet
- Mermaid and D2 support — Create flowcharts, sequence diagrams, Gantt charts, class diagrams, architecture diagrams, and more
- Local storage and projects — Diagrams are saved on-device and can be organized into projects; no account is required
- Optional Diagram Cloud sync — Sign in with an email link, GitHub, or Google to automatically back up local diagrams while retaining the on-device copy
Advantages
PrivyMermaid stores diagrams, source code, and settings on your device. It does not require cloud rendering or an account, and includes no analytics or third-party tracking SDKs. If you choose to sign in, Diagram Cloud can synchronize your diagrams; otherwise your workspace remains local. Pro AI connects only to the endpoint you configure.
Benefits
Draft diagrams wherever you are, export them into documentation, and use an AI endpoint you control to repair syntax or generate starting points. Keep working offline, or optionally sign in to keep a synchronized cloud copy of your diagrams.
PrivyMermaid Pro
PrivyMermaid Pro combines local-first editing with configurable AI assistance. Connect directly to a self-hosted Ollama or LM Studio server, or to an OpenAI-compatible endpoint you configure, to generate, fix, and refactor Mermaid or D2 diagrams.
Free vs Pro
| Capability |  Free |  Pro |
|---|---|---|
| Offline Mermaid & D2 Preview | ✅ | ✅ |
| Mermaid & D2 Source Editing | ✅ | ✅ |
| Theme Selection | ✅ | ✅ |
| Export (SVG, PNG, PDF, GIF, source) | ✅ | ✅ |
| AI Ask — Generate Diagrams | ❌ | ✅ |
| AI Fix — Auto-correct Syntax | ❌ | ✅ |
| LAN Ollama Connection | ❌ | ✅ |
| Streaming AI Responses | ❌ | ✅ |
| Optional Diagram Cloud Sign-in & Sync | ✅ | ✅ |
AI-Powered Diagramming
- Just Ask — Describe a workflow or system in plain English, and watch the AI generate Mermaid or D2 code for you
- Smart Fix & Refactor — Have a broken diagram or messy code? The "Fix" tool uses your local LLM to correct syntax errors and optimize layouts instantly
- Configurable AI endpoints — Connect to Ollama, LM Studio, or an OpenAI-compatible endpoint that you configure
- Real-time Streaming — Experience live code generation as the AI streams the response directly to your editor
Why PrivyMermaid Pro?
Perfect for power users running Llama 3, Mistral, Gemma, or another compatible model. Stop manually writing boilerplate code—let the AI endpoint you configure handle the syntax while you focus on the architecture.
Requirements
- iOS 17.0 or later (iPhone and iPad)
- AI endpoint (optional) — Required only for Pro AI generation, chat, fix, and refactor features. Configure Ollama, LM Studio, or an OpenAI-compatible endpoint reachable from your iPhone or iPad. Download Ollama at ollama.ai
iPhone Screenshots
iPad Screenshots
