FusionMD — Privacy Policy
FusionMD is a Markdown document studio for macOS. This policy explains what FusionMD accesses, what leaves your device, and what is stored locally.
Summary
FusionMD does not collect personal data. Your documents are stored locally
as .fusiondoc files (a JSON document containing your Markdown text plus
metadata). Document content is never
sent to DataIsland. AI features are opt-in — either on-device via Apple Intelligence
(nothing leaves your Mac) or via OpenRouter (with your own API key and your explicit
consent). The Vocabulary panel sends a single selected word (never document content) to
two free public lookup APIs when you use its Thesaurus or Dictionary sections. FusionMD
has no server, no account, and no analytics.
Your Documents
FusionMD stores documents as .fusiondoc files on your Mac, in locations you
choose. The format is a UTF-8 JSON document containing your Markdown source (in its
text field) alongside variables, boilerplate, and theme metadata — your content
is always recoverable without FusionMD, and a plain Markdown export is one click away via
File ▸ Save As ▸ Markdown. Documents are never transmitted to DataIsland.
What Leaves Your Device
OpenRouter (Optional — Opt-In Only)
FusionMD can optionally use the OpenRouter API to provide AI writing assistance. This feature:
- Is disabled by default
- Requires you to supply your own OpenRouter API key in Settings → AI
- Sends the active document or selected text to OpenRouter's servers when you invoke an AI action (generate, refine, summarise, etc.)
- Is governed by OpenRouter's privacy policy
DataIsland does not receive or store any document content sent through OpenRouter. Your API key is stored only in your macOS Keychain.
Apple Intelligence (Optional — Opt-In Only)
On supported hardware (Apple Silicon Mac, macOS 26, Apple Intelligence enabled), FusionMD can use Apple Intelligence for AI writing assistance. Apple Intelligence processes everything on-device. No document content leaves your Mac via this path. Apple Intelligence is governed by Apple's privacy policy.
Vocabulary Lookups (Thesaurus & Dictionary)
The Vocabulary panel's Thesaurus and Dictionary sections send the single word you've selected — never your document content — to two free, key-free public APIs: Datamuse (synonyms/antonyms) and Free Dictionary API (definitions). This happens whenever you select a word in that panel, independent of whether any AI feature is configured. The Overused Words analysis in the same panel is separate and runs entirely on-device via Apple's Natural Language framework.
No Other Outbound Network Activity
Outside of the AI features above and the Vocabulary lookups just described, FusionMD makes no outbound network connections. Every other feature — Markdown editing, templates, proofreading, style analysis, screenplay mode, and all export formats — works fully offline.
What Is Stored Locally
- Documents — stored as
.fusiondocfiles in user-chosen locations - Templates — stored as
.fusiontemplatefiles - Settings and preferences — stored in UserDefaults, local only
- OpenRouter API key (if provided) — stored in macOS Keychain
- Recent documents list — stored in UserDefaults, local only
None of this data is synced to iCloud by FusionMD or transmitted to DataIsland. (If you store documents in an iCloud-backed folder, iCloud's own sync applies under Apple's privacy policy.)
Analysis Tools
FusionMD includes eight document analysis tools (proofreader, readability, style clarity, grammar, etc.). All analysis runs locally on your Mac using system frameworks and built-in rules. No document content is sent to any server to perform analysis.
IDML Export
IDML export generates a structured file on your Mac from your document content. The export process is local. No document content is transmitted to DataIsland or any server.
What FusionMD Does Not Do
- Does not send document content to DataIsland or any server (except OpenRouter if enabled)
- Does not require an account or login
- Does not collect analytics or send crash reports to DataIsland
- Does not share any data with third parties for advertising
- Does not sync documents to any DataIsland cloud service
Children's Privacy
FusionMD is not directed at children under 13. We do not knowingly collect information from children.
Changes to This Policy
If we make material changes to this policy, we will update the "Last updated" date above. Continued use of FusionMD after changes constitutes acceptance of the updated policy.
Contact
Questions about this policy:
support@dataisland.com
DataIsland Software LLC