Signal vs WhatsApp: What End-to-End Encryption Actually Protects (And What It Doesn't)

End-to-end encryption is the most important privacy technology most people use — and one of the most misunderstood. "End-to-end encrypted" is treated as a binary property. Either an app has it or it doesn't. If it has it, your messages are private. That's the common understanding. The reality: E2EE protects message content in transit. It says nothing about what the app does with your data before encryption, what metadata it collects, who owns your keys, or what the company's legal obligations are when the government comes asking. Signal and WhatsApp both offer end-to-end encryption. They are not equivalent privacy tools. Understanding why requires understanding what E2EE actually does — and what it doesn't. What End-to-End Encryption Actually Does E2EE means the message is encrypted on your device, travels encrypted through the provider's servers, and is only decrypted on the recipient's device. The provider's servers relay encrypted bytes they cannot read. Cryptographically, this is i