Tuta — #2 Alternative to Gmail / Outlook
Quantum-resistant end-to-end encrypted email and calendar built in Germany
Tuta encrypts subject lines, message bodies, attachments, contacts, and calendars client-side using hybrid post-quantum cryptography (TutaCrypt) with open-source desktop and mobile apps that avoid Google Push.
License: GPL-3.0 (Clients) · Pricing: Freemium · Compare all Gmail / Outlook alternatives · Official Website