Encrypted messenger
When they take your phone, they read nothing.
LaSi encrypts your conversations end to end, and it also protects the phone once it's out of your hands. Locked, the app holds only ciphertext: the key lives in memory and is gone when it locks.
- End-to-end encrypted
- No phone number
- Key only in memory
- A relay with no disk
How it works
Built for the day your phone is out of your hands.
Good messengers already encrypt the conversation on its way. LaSi also takes care of what stays on the device.
A seized phone
Locked, it's only ciphertext.
With the app locked, your conversations, contacts and keys stay encrypted. The key never goes to disk in the clear, nor to the system's keychain.
- It locks 30 seconds after you leave the app, and right away in high-risk mode.
- It locks if the phone is snatched from your hand or falls.
- You type the password on LaSi's own keyboard: the system keyboard never sees it.
Duress password
A password for when they force you.
If someone forces you to open the app, a second password opens a decoy vault and wipes the real one. If you want, it also quietly alerts your trusted contacts.
- Remote wipe: the contacts you authorize can wipe the vault.
- Password only, at the hours you choose: then biometrics won't open the app.
- Panic gesture, on Android: five presses on the volume key lock the app.
No phone number
Nobody needs your number.
To talk, each of you reads the other's card. In person, one shows the QR and the other scans it. From afar, you swap cards and check the code on a call. Your address book never goes to any server.
A server with no disk
The relay keeps nothing.
The relay holds messages only in memory until they're delivered, and writes nothing to disk. It sees encrypted packets, never what's written. It works over Tor too.
No fine print
What LaSi doesn't protect
No app protects everything. These are the limits, stated up front.
- A phone taken with the app open, before it locks.
- Spyware installed on the device beforehand.
- The other side: what your contact keeps, shows or leaves on their phone.
- With biometrics on, whoever forces your finger or face opens the app. That's what the panic gesture and "password only" hours are for.
LaSi hasn't had an external audit yet. It comes before the public release.
For families, offices and companies
Your own relay
By default everyone uses LaSi's relay. A family, an office or a company can have a relay of its own: the metadata of who talks there never mixes with anyone else's.
Managed relay
We run the server. Brazil first; other countries later.
- Ready to use: in the app, type the relay's address and confirm.
- The license renews by itself.
- Nothing on disk, like LaSi's relay.
- No Tor yet: people in Tor mode can't reach this relay.
Price coming soon
I want a managed relayLicense for your own relay
For those who already have a server and want to run LaSi's relay on it.
- The setup guide comes with the license.
- The license renews by itself while your plan is active.
Price coming soon
I want a licenseWith either one, iPhone notifications go through LaSi's relay, without the message. If the plan lapses, the relay keeps going for 30 more days, then stops working in the apps. A managed relay keeps each client's metadata apart, but it runs on a LaSi machine: a breach of that machine, or a request from the authorities to LaSi, reaches every relay on it. To keep the metadata on a machine of your own, run your own relay.
Against the fake-lawyer scam
Verified professional seal
LaSi checks the professional's registration on a video call, with their professional board ID, and signs a seal bound to their key. Clients see a verified badge next to the name, and a tap shows the registration.
The Brazilian bar (OAB) first. Doctors (CRM) and psychologists (CRP) follow, with the same process.
Price coming soon
I want the sealExample
LaSi is coming soon to the stores.
When it's on Google Play and the App Store, the links show up here. Relays and the seal are sold only on this site.
Talk to usWrite to contato@lasimessenger.app. Replies come from lasi.contato@proton.me: any other address claiming to speak for LaSi isn't ours.