How to Choose a Private Journal App

Almost every journal app calls itself private. The useful question is: private from whom, and how?

A journal holds the things you wouldn't say out loud, so it's worth five minutes to check what an app actually does with your words. These seven questions cover what matters. We've answered each one for E-diary too, honestly, including where other apps make a different trade-off.

1. Where is the encryption key kept?

"Encrypted" can mean very different things. There are two common models:

• End-to-end (zero-knowledge) encryption: only your device holds the key. The company can't read your entries, but if you forget your password, your journal is usually gone for good.
• Encryption at rest: entries are encrypted in the database and the key is kept separately on the server. A leaked database or backup is unreadable, and you can reset a forgotten password without losing anything. The trade-off is that the service could, in principle, decrypt your entries.

Neither is wrong. Pick the one that matches your biggest fear: someone reading your journal, or losing it. E-diary uses encryption at rest (AES-256), because we think losing years of writing to a forgotten password is the more common disaster. Our security page explains the details.

2. What exactly is encrypted?

Often only the entry text is encrypted, while titles, tags, and dates are stored as plain text so search and filters work. That's a reasonable design, but you should know about it so you can keep sensitive details out of titles. In E-diary, entry text is encrypted, and titles, moods, tags, and dates are not.

3. How much personal data do I have to give?

A journal doesn't need your name, birthday, phone number, or contacts. The less you hand over, the less there is to leak. E-diary asks for an email address and a password, and nothing else.

4. How does the company make money?

If an app is free and shows ads, your attention or data is part of the product. Look for a clear statement that your data is never sold or used for advertising. E-diary has no ads and never sells data.

5. Is everything private by default?

Some journal apps include social features. That's fine if sharing is opt-in for each entry. Check that a new entry starts private and that nothing is shared unless you choose it. In E-diary every entry starts private, and you can choose to share individual entries with followers, by link, or publicly.

6. Does it work offline?

If you write on trains, planes, or anywhere with patchy signal, offline support matters. Check whether offline entries sync automatically once you're back online. E-diary works offline in the browser and syncs when you reconnect.

7. Can I take my journal with me?

You should be able to export everything in a standard format at any time. If you can't leave, you don't really own your journal. E-diary lets you export all of your entries whenever you like.

Bonus: can you check the claims?

Open-source apps let anyone inspect how data is handled, which is a strong sign that the privacy claims are real. E-diary's code is public on GitHub.

The short version

• Decide whether you fear someone reading it or you losing it, and choose the encryption model to match.
• Know which parts are encrypted.
• Give as little personal data as possible.
• Avoid ad-funded journals.
• Make sure entries are private by default, it works offline, and you can export everything.