When it comes to staying away from the prying eyes and eavesdropping ears of spies and hackers, perhaps no one knows better than Edward Snowden, the whistleblower who has spilled it all and is now also trying to stay away from said people’s reach. So when he openly endorses on Twitter (yes, he is on Twitter, of all places) WhisperSystem’s Signal app, now on Android, then you know, with a bit of confidence but perhaps also a grain of salt, that your text messages and voice calls will be secure and private.
Signal has actually been around for quite some time now. July last year, WhisperSystems, who develops the app, released it for iOS with a promise of an Android version soon. Apparently, “soon” meant almost 16 months. But now the wait is over and users who prefer to keep their private matters private can take advantage of the promise as well.
Signal is actually the combination of two existing apps, TextSecure and Redphone, both offering private connections for text messaging and voice calls, respectively. Considering how communication apps go these days, it made sense to combine them under a single roof. In theory, it should also make source code maintenance a lot easier.
Signal offers end to end encryption of messages and calls. This means that neither WhisperSystems nor anyone else will be able to eavesdrop on those at any stage of the communication. At the same time, Signal offers ease of use as it uses the owner’s numbers and phonebook stored on the phone itself, removing the need for separate and potentially hackable logins and accounts.
As the new Signal Android app starts to roll out to the public, users with installed TextSecure and Redphone apps will be prompted with the changes. To be more precise, the TextSecure app will actually be automatically updated to Signal, while those Redphone will be prompted to install the new Signal app. Signal is an open source application, so its source code is free to look at and audit by experts.