Subprocessors List

The third parties that process data for the Letro platform, website and sales process — who they are, what they handle, where, and under which safeguard.

Insights That Drive Secure Communication Forward

Last updated: 8 September 2026. Letro Tech GmbH (Chaltenbodenstrasse 8, 8834 Schindellegi, Switzerland) uses the third parties below to operate the Letro platform, its website and its sales process. Message content and attachments are end-to-end encrypted on the sender's device; no subprocessor can read them. The table states what each provider handles.

Platform subprocessors

Providers that touch Letro production systems or product data.

EntityFunctionLocation of processingData categoriesSafeguard
Infomaniak Network SA
Geneva, Switzerland
Hosting of Cloud and Dedicated homeservers and encrypted backups (one-week rolling)SwitzerlandEncrypted message content and attachments (ciphertext); delivery and audit metadata; account dataSwiss provider; Swiss Federal Act on Data Protection (FADP). No cross-border transfer.
Amazon Web Services EMEA SARL
Luxembourg
Object storage (Amazon S3)Switzerland (AWS Europe – Zurich region, eu-central-2)Encrypted files and attachments (ciphertext)Data stored in Switzerland; AWS Data Processing Addendum incorporating Standard Contractual Clauses.
Functional Software, Inc. (Sentry)
San Francisco, USA
Error and crash reporting for the Letro apps and homeserverEuropean Union (Sentry EU data region, Germany)Technical diagnostics: device and app version, error traces, pseudonymous user and session identifiers. No message content.EU data residency; Data Processing Addendum with Standard Contractual Clauses.
Twilio Inc. (SendGrid)
San Francisco, USA
Transactional email (account verification, notifications)United StatesEmail address, name, content of transactional emails (for example verification codes). No message content.Data Processing Addendum with Standard Contractual Clauses; provider certified under the EU-U.S. and Swiss-U.S. Data Privacy Framework.

Website and sales subprocessors

Providers used for letro.com, help.letro.com and our sales process. They do not receive product data.

EntityFunctionLocation of processingData categoriesSafeguard
Cloudflare, Inc.
San Francisco, USA
DNS, content delivery and security for letro.com and help.letro.com; cookie-consent managementGlobal edge network (request served from the nearest data centre)IP address, request metadata, cookie-consent choicesData Processing Addendum with Standard Contractual Clauses; provider certified under the EU-U.S. and Swiss-U.S. Data Privacy Framework.
HubSpot, Inc.
Cambridge, USA
CRM, website forms and sales emailUnited States / European Union (per HubSpot data hosting)Business contact details of prospects and customers, form submissions, correspondence with Letro salesData Processing Addendum with Standard Contractual Clauses; provider certified under the EU-U.S. and Swiss-U.S. Data Privacy Framework.
Surfe SAS
Paris, France
Business-contact data enrichment for sales prospectingEuropean UnionBusiness contact details of prospects (name, role, company, business email)EU provider; GDPR. Switzerland–EU adequacy.

Change log

  • 8 September 2026 — First published list, replacing the previous image-only version. Seven providers listed.

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