Privacy & Security

Phase was built with one principle: your thoughts are sacred.

The Short Version

Your journal entries are encrypted on your device before storage
We use AES-256-GCM — the same encryption trusted by governments
No data ever leaves your device — there are no servers, no cloud, no accounts
No AI, no analytics, no tracking — we don't even know you exist
You can export your data anytime — no lock-in, ever

How Encryption Works

Encryption Standard

Phase uses AES-256-GCM (Advanced Encryption Standard with Galois/Counter Mode):

256-bit keys — 2²⁵⁶ possible combinations (more than atoms in the universe)
GCM mode — Provides both encryption AND authentication
Unique IV per entry — Each entry uses a fresh random initialization vector

This is the same standard used by the US Government for classified information, banking institutions, and password managers like 1Password and Bitwarden.

Two Security Modes

1. Device-Bound Mode

A random encryption key is generated and stored in your browser
Fastest option — unlock instantly
Data only accessible on this device/browser
Best for: Personal devices you trust

2. Passphrase Mode

You create a passphrase (we recommend 4+ random words)
Key is derived using PBKDF2-SHA256 with 600,000 iterations
Passphrase is never stored — only a verification hash
Portable — access your journal on any device with your passphrase
Best for: Maximum security, multiple devices

What's Encrypted

Data	Encrypted?	Why
Entry text	Yes	Your private thoughts
Mood	Yes	Mental health state is sensitive
Tags	Yes	Tags like "anxiety" or "therapy" are sensitive
Activities	Yes	Behavioral patterns are sensitive
Photos	Yes	Attached images are sensitive
Weather	Yes	Can reveal location patterns
Thought records (CBT)	Yes	Therapeutic data is sensitive
Timestamps	No	Needed for date organization
Follow-up reminders	No	Needed for scheduling notifications

All personal content is encrypted at rest. Only structural fields like timestamps and entry IDs remain unencrypted so the app can organize your data without decrypting everything.

No Cloud, No Servers

Phase has no backend servers. Zero.

No user accounts
No authentication servers
No data sync
No analytics endpoints
No crash reporting
No telemetry

Your data is stored in IndexedDB — a database built into your browser. It never leaves your device unless YOU export it.

How Backups Work

When you export a backup:

Your encrypted entries are packaged into a JSON file
The file downloads to YOUR device
No data is transmitted anywhere

The backup file contains your encrypted data — it's still protected even if someone finds the file.

No AI, Ever

Many journaling apps now use AI to "enhance" your experience. We don't.

Why not?

AI requires sending your text somewhere to process it
"On-device AI" still creates models from your data
Your journal is for YOU, not for training algorithms
We believe your thoughts should stay in your head (and your encrypted journal)

We will never:

Add AI "insights" that analyze your writing
Use your entries to train models
Sell or share your data with AI companies
Add "smart" features that compromise privacy

What We Can't Protect Against

We're honest about our limitations:

Device compromise — If malware has access to your device, all bets are off
Weak passphrases — "password123" won't protect you (use 4+ random words)
Browser vulnerabilities — Keep your browser updated
Physical access — Someone with your unlocked device can see your entries
Memory forensics — Advanced attackers could potentially read keys from RAM

For most people, Phase provides more than enough protection. If you're a journalist, activist, or have nation-state adversaries, consider additional security measures.

Questions?

If you have security questions or concerns, please reach out through the feedback form inside the app. We take security seriously.

Remember: Your mental health matters. Your privacy matters. We built Phase to protect both.

— A fellow MH warrior