Comparison

PrivyMermaid vs CodePad!

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

Head to head
About

PrivyMermaid

This privacy-focused editor allows developers and technical writers to create, edit, and preview diagrams completely offline. Your sensitive data remains on your device, ensuring maximum security and control over your diagrams.

Highlights
  • 100% Private & Offline diagram editing
  • Instant offline diagram rendering
  • No cloud sync for enhanced data privacy
  • Live preview of diagram changes
  • Multiple theme selections
  • Full Mermaid syntax support
Features
Read full description

PrivyMermaid is a privacy-focused diagram editor for developers, technical writers, and teams who work with Mermaid and D2. Create, import, edit, organize, preview, and export diagrams on your iPhone or iPad. The Mermaid and D2 renderers are bundled in the app, so you can keep working without an internet connection. Your diagrams stay on your device by default; no diagram source is sent to a rendering service. Key Features: Mermaid + D2, fully offline Two diagram languages: Create and preview Mermaid or D2 diagrams, including flowcharts, sequence diagrams, Gantt charts, architecture diagrams, and more. Local rendering: Visualize diagrams without an internet connection. The rendering engines run in the app, not on a diagram server. Import and export: Work with Mermaid (.mmd) and D2 (.d2) source files, then export SVG, PNG, PDF, or GIF. Projects and templates Organize your work: Keep diagrams in native projects and switch between documents quickly. Built-in templates: Start from ready-made diagram examples, clearly labeled for Mermaid or D2. Live preview and themes: See manual edits immediately and choose a Mermaid or D2 theme plus your preferred preview background. Privacy on your terms Local by default: Diagrams are stored locally and no account is required for offline editing. Optional Diagram Cloud sync: If you choose to sign in, diagrams can sync to your Diagram Cloud account. Your local copy remains available offline. Why PrivyMermaid? Keep technical documentation close at hand without depending on a browser tab or a hosted rendering service. PrivyMermaid is a lightweight, private way to diagram on the go. Note: For AI-assisted Mermaid and D2 generation, questions, and fixes using your local LLM, check out PrivyMermaid Pro (in-app: tap the Pro tab or open the Pro panel; or download the separate PrivyMermaid Pro app).

About

CodePad!

Features
Read full description

CodePad is a lightweight code viewer and editor for your iPhone and iPad that opens your files directly โ€” not a copy. Browse to any code or text file (HTML, JSON, Swift, Python, JS, and more), view it instantly, and edit it in place with a single tap. Changes save straight back to the original file, so what you edit is what stays on disk. โ€ข Open files directly from the Files app โ€” no copying, no import step โ€ข Instant syntax-aware viewing for common code and markup files โ€ข One-tap edit mode with clear save/cancel controls โ€ข Saves changes directly to the source file โ€ข Simple, distraction-free interface built for quick edits CodePad is built for anyone who needs to peek at or tweak a code file on the go โ€” students, developers, and anyone managing text-based files on their iPhone or iPad.

Screenshots

PrivyMermaid4 screens
CodePad!4 screens

Verdict

The call

The clearest difference is in-app purchases: CodePad! at none against PrivyMermaid's 2. PrivyMermaid's advantage is update cadence (every 2 weeks vs every 4 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. PrivyMermaid sells 2 one-off in-app purchases. CodePad! asks for nothing beyond the download.

UpkeepUpdate frequency

PrivyMermaid ships an update every 2 weeks, CodePad! every 4 weeks. The most recent releases landed on October 26, 2026 and October 29, 2026 respectively.

Scorecard2 real differences ยท 6 level
PrivyMermaid versus CodePad!: the parameters behind the verdict, then further details
ParameterPrivyMermaidCodePad!
PriceFreeFree
Positive reviews100.0% of reviewsโ€”
Update frequencyEvery 2 weeks โ€” betterEvery 4 weeks
AdsNoNo
In-app purchasesYesNo โ€” better
MonetizationFreeโ€”
DevicesiPhone, iPad, Mac โ€” betteriPhone, iPad
Requires iOS17.0 โ€” better18.0
Further details โ€” not scored
Size39 MB6 MB
Age rating4+4+
DeveloperGUOYU WANGJIN SIK CHOI

In-app purchases

2 purchases

PrivyMermaid

One-time2
  • PrivyMermaid Pro$4.99
  • PrivyMermaid Pro$9.99
None

CodePad!

No in-app purchases

Questions

Is PrivyMermaid free?
PrivyMermaid is free to download, with in-app purchases available.
Is CodePad! free?
CodePad! is free to download, with no in-app purchases.
Do PrivyMermaid or CodePad! have ads?
Neither PrivyMermaid nor CodePad! shows ads.
Which is updated more often, PrivyMermaid or CodePad!?
PrivyMermaid ships an update every 2 weeks, and CodePad! every 4 weeks. Most recently, PrivyMermaid was updated on October 26, 2026 and CodePad! on October 29, 2026.

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