Your conversations.
Only yours.
Padlock brings together messages, voice and video calls, a file vault and a crypto wallet, all encrypted on your phone. No phone number, no email, and we can't read anything.
Features
Encrypted messages
Text, voice notes and photos protected by the Double Ratchet protocol: every message uses a fresh key.
Voice and video calls
Encrypted calls. With "Protect my IP" on (default), the other person never sees your IP address.
No phone number
Your identity is an ID generated mathematically on your phone, not linked to your name or number.
Forensic auto-destruct
Messages delete themselves within 24 hours at most and are overwritten on disk.
Secure Vault Files
Photos and documents live in a separate vault with its own password, never inside the chat.
Panic Room
One button instantly destroys your identity, chats, files and wallet on this phone.
Security
Everything is encrypted on your phone before it leaves. Our server is a blind courier: it knows where to deliver a sealed packet, but cannot open it.
| Function | Algorithm |
|---|---|
| Identity and signatures | Ed25519 |
| Key agreement | X25519 |
| Messages | Double Ratchet, HMAC-SHA-256, AES-256-GCM |
| Metadata | Sealed sender, padded packet sizes |
| Calls | WebRTC DTLS-SRTP, Ed25519-signed signalling, safety number |
| Local vault | AES-256-GCM, Argon2id (64 MiB), device secret in Android Keystore |
Quantum computers: AES-256 is considered quantum-resistant. Like almost every app today, the key exchange (X25519) is not yet post-quantum; a hybrid X25519 + ML-KEM upgrade is planned. Screenshots are blocked, sessions lock after 15 minutes, and there is no password recovery or backdoor for anyone, including us.
CryptoVault (Padlock + CryptoVault plan)
A non-custodial wallet: your keys are created and stored only on your phone. Send and receive ETH, POL and USDC on Ethereum, Polygon and Arbitrum One. Share your address with a contact inside the encrypted chat. Sends to the wrong network are blocked. Your 24-word recovery phrase is the only way to restore the wallet, so write it on paper.
Padlock is not a bank, exchange or custodian and gives no investment advice. Blockchain transactions are irreversible.
About
Padlock is built by an independent developer based in Portugal (EU). No investors, no ads, no data sales. Two yearly plans through Google Play: Padlock, USD 9.99/year with 7 days free (messages, calls, photos, Secure Vault Files), and Padlock + CryptoVault, USD 49.99/year with no free trial. We plan to publish the source code after launch.
Contact: padlockapp@proton.me