Security model

Last updated: 7 June 2026

Espero's job is to translate your messages so people who speak different languages understand each other. That shapes our security model — and we'd rather explain it plainly than imply protections we don't provide.

The honest version, up front

Your messages are encrypted in transit (TLS) and encrypted at rest on our servers.
To translate a message, our server has to read its text — so Espero is not end-to-end encrypted. It is “encrypted” in the same sense as a normal cloud service, not zero-knowledge. We say this clearly so you're never misled.
We use your messages only to deliver and translate them — never to sell, to show ads, or to build advertising profiles.

Why isn't it end-to-end encrypted?

End-to-end encryption means the server can never read your messages. Live translation means the server (and the AI translation service) must read each message to turn it into every reader's language. Those two goals are fundamentally opposed — you cannot translate text you cannot read. Espero is built around translation, so it does not offer end-to-end encryption, and we won't claim a protection we don't actually provide.

How translation handles your data

Message text — plus transcripts of voice notes and descriptions of images — is sent to our translation provider (Google's Gemini API) to be turned into each recipient's language. One request produces every language at once. The content is processed only to produce the translation; it is not used to train models, and we don't sell or monetise it.

What the server can and can't do

	Espero
Encryption in transit	Yes — TLS
Encryption at rest	Yes
Server can read messages (to translate)	Yes — by design
Sold or used for advertising	Never
Used to train AI models	No
Report & block · delete your account	Yes

What we don't do

No advertising, no ad profiles, no selling your data.
No using your messages to train AI models.
No requiring your phone's contact list; discovery by username or invite link works without it.

Infrastructure

Messages, accounts and media live in our database (Convex) hosted in the European Union (Ireland), behind TLS and access controls. Payments are handled by Apple, Google or Stripe — we receive only your subscription status, never card details.

Responsible disclosure

Found a security issue? Please email security@espero.live before disclosing publicly. We're grateful for reports and will work with you on a fix.

Honesty note

Security claims about messaging deserve scrutiny. Espero gives you encryption in transit and at rest and treats your messages with care — but it is not end-to-end encrypted, because translation requires reading your messages. We will keep this page accurate and will never claim a protection we don't provide.

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