Open Source End-to-End Encryptions for Android

Open-source password manager with AES-256 encryption and device sync. Store and access encrypted logins across platforms like iOS and Android.

An encrypted messaging app focused on privacy, supporting texts, calls, photos, videos, files, and group chats, with no ads or trackers.

LocalSend is a free, open-source, cross-platform file-sharing tool designed to securely share files and messages with nearby devices over your local network without needing an internet connection. Here are some of its key features:

Secure Swiss-based email with end-to-end encryption and zero third-party access. Available across devices, offering a free version to promote privacy.

Enhance privacy with a secure, portable browser that hides your IP and encrypts connections on multiple platforms, maintaining anonymity.

On-premises file sync, universal access, integrated collaboration, real-time communication with privacy and data control focus.

Open source note-taking app with Markdown support, to-do integration, and synchronization with cloud services like Dropbox and OneDrive.

A secure collaboration app with end-to-end encryption and interoperability across web, desktop, and mobile. Includes chat, voice, and video calls.

Open-source suite for editing documents, spreadsheets, presentations, forms, and PDF files with co-editing modes, plugin support, AI assistant, and integration across 40+ platforms.

Swiss-based VPN that ensures online privacy with a high-speed network, advanced encryption, and no-logs policy, offering a free version. Supports multiple platforms and unblocks content worldwide.

Open source tool for secure remote access and screen sharing, supporting cross-platform use and self-hosting for complete data control.

Aegis Authenticator is a free, secure and open source app to manage your 2-step verification tokens for your online services.

End-to-end encrypted note-taking with offline access, unlimited sync across devices, tagging, passcode and biometric security, plus advanced premium privacy features.

Mullvad is a VPN service that helps keep your online activity, identity, and location private.

Protect your accounts with Proton Authenticator, a private and secure cross-device two-factor authentication (2FA) that works offline. Created by Proton, the creators of Proton Mail, Proton VPN, Proton Drive, and Proton Pass.

ente's Authenticator app helps you generate and store 2 step verification (2FA) tokens on your mobile devices.

Cryptomator provides transparent, client-side encryption for your cloud. Protect your documents from unauthorized access. Cryptomator is free and open source software, so you can rest assured there are no backdoors.

End-to-end encrypted app for email, calendar, and contacts, requiring no personal data, with open source code and quantum-resistant security.

Matrix defines a set of open APIs for decentralised communication, suitable for securely publishing, persisting and subscribing to data over a global open federation of servers with no single point of control.

A password manager that ensures identity and password security with rigorous, end-to-end encryption, built by scientists from CERN, and recommended by the United Nations.

Notesnook is a simple and cross-platform private notes app that keeps your notes organized and synced on your phone, tablet and computer. Take notes, capture ideas, create to-do lists, keep a journal, write your assignments and manage projects, we have got you covered.

K-9 is an open source email client for Android with multi-folder sync, email signatures, Bcc-to-self, return-address configuration, keyboard shortcuts, Exchange Support, message flagging, IMAP deletes, saving attachments, configurable notifications and more.

Open-source, end-to-end encrypted backup and sharing for photos and videos, with multi-platform sync, original quality, privacy controls, and collaborative albums.

Emphasizes privacy with end-to-end encryption, Proton Drive safely stores, synchronizes, and shares files across devices via web and mobile applications.

Simple, fast VPN tunnel utilizing state-of-the-art cryptography, minimal codebase for security, supports cross-platform use, offers IPv4/IPv6, and ease of deployment.