Threema

Threema is a secure instant messaging application offering end-to-end encrypted text, voice calls, and file sharing across multiple platforms. Key features include GDPR-compliant operation, the ability to verify contacts via QR codes, and the option to use the app anonymously without providing a phone number or email. This application is suitable for individuals and organizations prioritizing secure communication and data privacy, particularly those needing a messenger compliant with European data protection regulations.