Threema

The application provides end‑to‑end encrypted instant messaging for individuals, businesses, and other organizations. All messages, voice calls, video calls, and file transfers are encrypted on the client side, ensuring that only the intended participants can access the content. The service is designed to comply with GDPR and follows a zero‑knowledge principle, meaning the provider does not retain personal data such as phone numbers or email addresses, and metadata is kept to a minimum.

For corporate use, the platform includes a management console that lets administrators configure user permissions and group settings centrally. It supports typical messenger features—structured group chats, encrypted voice and video calls—while maintaining the same privacy guarantees as the personal version. Companies can also deploy the software on their own infrastructure, giving them full control over data storage and compliance with strict security policies.

The solution is built in Switzerland and is distributed as open‑source code, allowing independent verification of its security claims. It targets users who need strong confidentiality, including sectors such as finance, healthcare, and government, as well as private individuals who want private, anonymous communication.