Messaging app Signal witnessed a meteoric rise in downloads after Facebook-owned WhatsApp updated its privacy terms, sparking privacy concerns from users. The app, which was also endorsed by billionaire Elon Musk, was downloaded almost 7.5 million times globally through the Apple App Store and Google Play store between January 6 and January 10, according to market intelligence firm Sensor Tower. This was a record for weekly - or even monthly - installs for Signal in its history. So what is Signal and how does it differ to other messaging apps? Signal is an independent, non-profit encrypted messaging service. It was first rolled out in July 2014 by American entrepreneur and computer security researcher Moxie Marlinspike but was later hosted by the non-profit Signal Foundation launched in February 2018. Signal is an open-sourced application where any user can check its software code to ensure there is no interference by any third-party company in the background and users’ confidential data is safe. “There are no ads, no affiliate marketers, and no creepy tracking in Signal ... so focus on sharing the moments that matter with the people who matter to you,” Signal says on its website. WhatsApp co-founder Brian Acton and former Twitter executive Mr Marlinspike launched the Signal Foundation in 2018 with Mr Acton pumping in initial funding of $50 million. A computer science graduate from Stanford University, Mr Acton founded WhatsApp in November 2009 with his friend Jan Koum after stints at Apple, Yahoo and Adobe. The messaging app was later acquired by Facebook in 2014 for $19 billion. Mr Acton left Facebook in 2017 after he was reportedly pressurised to monetise the service. Signal is financed through grants and donations, starting from a minimum of $3, offered by its users and privacy advocates globally. “We are not tied to any major tech companies, and we can never be acquired by one either ... development is supported by grants and donations from people like you,” Signal says on its website. About 810,000 users worldwide downloaded Signal on Sunday, an almost 18-fold increase compared with the downloads on January 6, according to research firm Apptopia. WhatsApp was installed by almost 1.2 million users on Sunday, down by nearly 7 per cent in daily installs compared with January 6 numbers. After downloading Signal from the app stores, users can set it up by adding their mobile number, entering the one-time-password, name and other basic details. Users can also create groups similar to those in WhatsApp by tapping on three dots on the top right corner of the app. They need to manually add at least one member to make it functional. Then go to the group settings and tap on ‘group link’ to get an invite link. This link can be shared with contacts on other platforms such as WhatsApp. Though it is an easier way to inform friends and family about Signal, it cannot import chats from other platforms. WhatsApp’s new privacy policy is being met with criticism since the social networking app is asking its users to share personal information with its parent company – Facebook – or have their accounts deactivated. However, users have become increasingly privacy conscious over the few years, often opting for technology that is encrypted. In November last year, Google announced it was rolling out a beta version of its Android messaging app that will depend on end-to-end encryption. End-to-end encryption ensures that no one, including Google and third parties, can read the content of messages as they travel between your phone and the phone of the person you are messaging, the Alphabet-owned company <a href="https://blog.google/products/messages/helping-you-connect-around-world-messages/">said</a>. "I trust Signal because it’s well built, but more importantly, because of how it’s built: open source, peer reviewed, and funded entirely by grants and donations. A refreshing model for how critical services should be built,” Jack Dorsey, chief executive of Twitter and Square, said.