Signal is primarily a mobile app, but desktop companion apps make it easy to keep the conversation going Instead, it creates a one-way cryptographic hash of your number and then generates an alert on your device when a friend has joined if the same hashed number appears in your contacts list. Know that Signal does not store or share your phone number, nor does it siphon up your contact lists.

That process can take some time, however. These desktop apps have improved dramatically and can even load a history of your messages when you log in. Emphasis on companion you need to register for Signal using a mobile phone. Signal is available as an Android app and an iOS app, with companion desktop apps for Linux, macOS, and Windows. The company moved quickly to secure its users and disclose the attack-which is what a company should do in this situation. Recently, an attack on a third-party service used by Signal to verify new signups potentially revealed the phone numbers and SMS verification codes of 1,900 users. Signal hasn't had smooth sailing when it comes to security. Apple Messages also use E2EE, but those messages can still be accessed by analyzing backups. Also, because Signal does not back up messages, it is resistant to both legal and malicious attempts to access cloud backups.

This was the least amount of information compared to competitors in the FBI document. This confirmed what Signal had long said: It can only provide the date a user signed up for the service and the last time the service was used. In late 2021, a document emerged outlining what information the agency could legally obtain from various messaging platforms. That said, it's disappointing that Signal does not have a bug bounty, which can help incentivize finding potentially dangerous vulnerabilities.Īn even stronger endorsement comes, ironically enough, from the FBI. Telegram's encryption scheme is far more controversial. While you might not trust those companies, they have vetted Signal's technology and found it worthy. Its core technology has also been implemented by Meta's and Google's messaging platforms, albeit optionally. The underlying technology called the Signal Protocol is open-source and has been evaluated by researchers.

I am not a cryptographer, but other, smarter people than I have examined Signal.

Signal app download