Open-source Android app sends encrypted messages over Bluetooth without internet or servers

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A developer has released Eccles Bluechat E2EE, an experimental Android messaging app that avoids the internet, user accounts, and central servers. Instead, it relies on Bluetooth for decentralized communication. The app uses end-to-end encryption built on ECDH, HKDF-SHA256, and AES-256-GCM, with keys protected by the Android Keystore. It also includes trust-on-first-use identity verification, encrypted local storage for messages and media, and Bluetooth-based voice and video calls. The project is open source, and its author is sharing the architecture, implementation details, and lessons learned.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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