Privacy & Security

HealthViewer is built around a single principle: your health data belongs to you, and only you.

Local-Only Storage

All data is stored in a single encrypted file (.hvdb) on your own device. There is:

No account required
No cloud sync or backup
No telemetry or analytics
No servers involved in normal operation

The .hvdb file never leaves your computer unless you explicitly copy or move it.

Encryption

The database is encrypted with AES-256-GCM, a military-grade symmetric cipher. Your password is never stored — it’s used with PBKDF2 key derivation to unlock the database each session.

Individual sensitive fields (lab values, notes, etc.) are encrypted at the field level in addition to the database-level encryption. If someone obtains your .hvdb file without your password, the data is unreadable.

AI features (appointment summaries, medication interpretation, PDF OCR fallback) are optional. When used:

The relevant data (e.g. your recent lab results for a summary) is sent to the AI provider you’ve configured
Your API key is encrypted in your local database
HealthViewer does not have its own servers; requests go directly from your device to the AI provider’s API
AI providers have their own privacy policies — review them before enabling

No data is sent to any AI provider unless you explicitly use an AI-powered feature.

What “After Visit Summary” PDFs Contain

When you upload a PDF from your patient portal, it is processed entirely on your device. The PDF bytes are read locally; nothing is uploaded to a server. If AI parsing is used as a fallback, only the extracted text (not the original PDF) is sent to the AI provider.

Database Backups

HealthViewer creates automatic backups of your database before major operations. Backup files are stored alongside your .hvdb file with a .bak extension, and are encrypted with the same password.

If you want to back up your data, simply copy your .hvdb file to another location (e.g. an encrypted external drive or a local Time Machine backup).