Signal is a cross-platform encrypted messaging service developed by the Signal Foundation and Signal Messenger. It uses the Internet to send one-to-one and group messages, which can include files, voice notes, images and videos.[16] It can also be used to make one-to-one and group voice and video calls,[17][18] and the Android version can optionally function as an SMS app.[19]
Signal uses standard cellular telephone numbers as identifiers and secures all communications to other Signal users with end-to-end encryption. The apps include mechanisms by which users can independently verify the identity of their contacts and the integrity of the data channel.[19][20]
Signal’s software is free and open-source. Its clients are published under the GPLv3 license,[12][13][14] while the server code is published under the AGPLv3 license.[15] The Android app also includes third-party components which are closed-source.[21][self-published source] The non-profit Signal Foundation was launched in February 2018 with initial funding of $50 million from Brian Acton.[22] Signal has more than 10 million downloads on Android.[23]
https://en.wikipedia.org/wiki/Signal_%28software%29
Knowing Brian Acton, creator of WhatsApp and its viral rival Signal
It has been an exciting week for Signal Messenger — between an endorsement from the world’s richest person and a 38% surge in downloads, some say the encrypted messaging app is having its moment.
This, after WhatsApp said it is tweaking its terms of use and privacy policy to share significantly more user data with Facebook. And there isn’t an opt-out option — you either accept the terms or stop using the app altogether.
But Signal and WhatsApp do have a common thread — their creator Brian Acton, who left the world’s largest messaging service after a rift with Facebook CEO Mark Zuckerberg over monetising the app. His early exit cost him $850 million.
Exit from WhatsApp
Facebook acquired WhatsApp in February 2014 for close to $22 billion, making Acton a billionaire. But he left less than four years later, in September 2017, due to his strained ties with Zuckerberg. The Facebook CEO wanted to monetise WhatsApp using targeting ads and commercial messaging, according to a Forbes report.
Ten months after his departure, the Cambridge Analytica scandal unfolded. Acton tweeted, “It is time. #deletefacebook”. He hasn’t tweeted since.
The creation of Signal
Acton took his motto of “no ads, no games, no gimmicks” at WhatsApp and created Signal Messenger Llc with Moxie Marlinspike of Open Whisper Systems in January 2018. The two-year-old app is entirely funded by grants and donation, which — according to Twitter CEO Jack Dorsey — is how such services should be built.
Signal today is considered the gold standard for privacy by journalists to whistleblowers. According to its website, American whistleblower Edward Snowden is a loyalist and uses the app every day.
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