Use case — WhatsApp alternative

As easy as WhatsApp.
Owned by the firm.

Encrypted, governed and auditable client messaging — instead of a personal chat app with a professional-secrecy problem.

Request a demoSee the architecture

Animation: in a consumer chat app, a signed draft is sent to an unsaved number, backed up to a personal cloud and forwarded on. The same exchange in Letro: a private workspace, a sender verified with PostNumber, an encrypted letter with the draft attached, and an audit record that is exported. Illustrative example with fictional names.

ProtocolEnd-to-end encrypted
HostingSwiss by default
ScopeClient and matter
RecordTimestamped, exportable
What it is

The same two taps for your client. A different answer for the firm.

A professional messaging app for client communication — end-to-end encrypted on the Matrix protocol, hosted in Switzerland, scoped by client and matter, and governed by the firm rather than by an employee’s phone.

WhatsAppConsumer app
Employee’s phone
One global inboxFamily groupClient A · signingClient B · KYC filesUnknown number
Leaves the firm
Consumer cloud · unknown residency
No firm control over retentionNo scope by client or matterNo record you can hand a regulator
→
LetroFirm workspace
Scoped rooms
Client A · matter 4471Client B · KYC onboardingInternal · deal team
E2EE · Matrix protocol
Swiss server · firm-governed
Retention and access set by the firmNothing bleeds between clientsTimestamped record, exportable on request
Why it belongs in Letro

Four things a personal phone cannot give you

01 — Scope

Scoped, not one global inbox

Conversations are organised by client, matter or team. Nothing bleeds between them.

02 — Control

Encrypted and governed

End-to-end encryption on the Matrix protocol, with the firm — not the individual — in control of retention and access.

03 — Calls

Calls included

HD voice and video calls run inside the Workspace or one-to-one.

04 — Hosting

Sovereign hosting

Swiss-hosted by default. Dedicated and Sovereign deployments put the server under your control, including air-gapped.

Keep client chat where the record is.

How Letro replaces WhatsApp

Same convenience for the client. Four steps for the firm.

01

Invite clients from the app

Clients install Letro and verify once with PostNumber.

02

Message where the record is

The quick question stays in the same channel as the documents it concerns.

03

Control the data

Retention, export and access are set by the firm, not by an employee’s phone.

04

Answer the regulator

When asked, produce the timestamped record of who said what, when.

Get started

Discuss your deployment model

Standard rollout, private infrastructure, or stricter residency and isolation requirements — Letro gives you a verified, evidential foundation for client communication.

Book a demoDiscuss deployment