Threema

Threema is a secure instant messaging application offering end-to-end encrypted text, voice calls, and file sharing across various 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 address. This application is suitable for individuals and organizations that prioritize secure communication and data privacy, particularly those needing a messenger that complies with European data protection laws.