Most Secure Diary App

Your Secret Diary
Stays Secret

Zendiary is the most secure diary app with passcode, Face ID, fingerprint lock, and AES-256 encryption. Even we can't read your entries. Your private thoughts deserve military-grade protection.

4.8 rating • 50,000+ users trust their secrets with Zendiary

Why You Need a Diary with Lock

Your diary contains your most intimate thoughts, fears, dreams, and secrets. A diary app with lock ensures that even if someone picks up your phone, they can't access your private world.

But here's what most people don't realize: a simple passcode isn't enough. If your diary data isn't encrypted, anyone with technical knowledge can extract it from your device. That's why Zendiary uses the same AES-256 encryption that banks use to protect financial data.

With Zendiary, your locked diary stays locked—even from us. We literally cannot read your entries, even if law enforcement asked. That's the level of privacy you deserve.

Multi-Layer Security Protection

Zendiary doesn't just lock your diary—it creates an impenetrable fortress around your thoughts

Passcode Lock

Set a custom PIN or password that only you know

Face ID / Face Recognition

Unlock instantly with your face on supported devices

Fingerprint / Touch ID

Quick and secure biometric authentication

AES-256 Encryption

Military-grade encryption for all your entries

Auto-Lock

Automatically locks when you leave the app

Secure Backup

Encrypted cloud backup - even we can't read it

Security Level Comparison

How Zendiary's security compares to other diary apps

Security LevelFeatureZendiaryOther Apps
BasicSimple Passcode
BetterBiometric LockSome
BestEnd-to-End EncryptionRare
UltimateZero-Knowledge Architecture

How Zendiary Protects Your Diary

1

Choose Your Lock Method

Set up passcode, Face ID, fingerprint, or combine multiple methods. Your choice, your security.

2

Entries Get Encrypted

Every entry is encrypted with AES-256 before being stored. Even if someone accesses your storage, they see gibberish.

3

Auto-Lock Engages

Zendiary automatically locks when you switch apps or your screen turns off. No chance of leaving it open.

4

Only You Can Unlock

Decryption only happens with your authentication. Not even Zendiary servers can access your content.

Diary with Lock FAQ

What types of locks does Zendiary offer?

Zendiary offers passcode/PIN, Face ID (iOS), Face Recognition (Android), fingerprint/Touch ID, and pattern lock. You can combine multiple methods for maximum security.

What if I forget my passcode?

If you have biometric authentication enabled, use that to access your diary. For account recovery, reset through your email. Locally encrypted entries without backup cannot be recovered—this is a security feature.

Can someone read my diary if they steal my phone?

No. Zendiary has its own independent lock separate from your phone's lock screen. Plus, all entries are AES-256 encrypted, making them unreadable without your authentication.

Is the lock feature free?

Yes! All lock features (passcode, biometric, encryption) are completely free. We believe privacy is a right, not a premium feature.

How is Zendiary more secure than other diary apps?

Most diary apps only offer a simple passcode overlay. Zendiary uses zero-knowledge architecture with AES-256 encryption—even we cannot read your entries. Your data is encrypted before storage, not after.

Lock Your Secrets Away Forever

Join 50,000+ people who trust Zendiary with their most private thoughts. Free forever.