Words by ITV News Multimedia Producer Ann Yip
Many are switching to messaging apps Signal and Telegram, which have surged to the top of the charts of app stores.
Signal’s registration system even crashed on January 7, after many new users tried to join the service.
Tech billionaire Elon Musk prompted Twitter followers to "Use Signal" last week, with the app also being endorsed by Twitter CEO Jack Dorsey and Edward Snowden.
ITV News spoke to cybersecurity expert Zak Doffman, CEO of security system supplier Digital Barriers, to find out whether or not users should be worried about their privacy on Whatsapp and whether they should switch to Signal and Telegram.
What do the new privacy rules mean for Whatsapp users?
Whatsapp’s new privacy terms, which will take effect on February 8, suggests more data could be shared with Facebook, which owns the messaging app.
But following the backlash, the app has since clarified that users’ private messages with friends and family will still be end-to-end encrypted and will not be shared with Facebook.
The data that will be shared with the social media giant may be messages with businesses that use Facebook hosting services for their communication. Whatsapp has assured users that conversations with such businesses will be clearly labelled.
How worried should Whatsapp users be about their privacy?
“If you’re using Whatsapp now, it’s secure. Most people have plenty of apps that collect more data than Whatsapp,” he said.
But he is concerned that the whole furore may undermine public confidence in end-to-end encryption technology.
He said: “Whatsapp is the reason we have end-to-end encrypted messaging. It overtook SMS, which is insecure technology. What’s taken place undermines confidence in that. And I think that’s a real issue.”
Mr Doffman added the reasonable worry is that the new policy could be the beginning of a series of changes. He said it is possible Whatsapp might share more data with Facebook in the future as shopping and payments become a bigger part of its platform.
He also acknowledged that although Whatsapp does not share much data with Facebook, it does collect a lot of metadata - and this is not a new thing. Crucially, the metadata is linked to individual users - this could be information like when users log in, their location, who they contact and when messages are sent.
He said: “They say they don’t share information with Facebook, but it is being collected. Whatsapp has hesitated to be specific about what they collect, what Facebook sees and doesn’t see.
"There’s a lot of stuff around usage data which Whatsapp says it collects to run the platform, but critically, it links the data to you.”
He said Whatsapp currently doesn’t share users’ metadata with Facebook because “it’s simply a policy, but it can do what it likes”.
And perhaps what people should be worried about is that Facebook has talked about integrating Whatsapp, Messenger and Instagram, Mr Doffman said.
He said another worry is Whatsapp backs up users’ messages on clouds hosted by Google or Apple, and these messages are not encrypted once stored on the server.
What is Signal, and should people switch to it?
Signal is a non-profit app developed by the Signal Foundation and Signal Messenger, both founded by Moxie Marlinspike and Brian Acton. Owners have said it can never be acquired by a major tech company and development is supported by grants and donations.
Like Whatsapp, the app uses your phone's data connection and users can share text, voice messages, photos, videos, GIFs and files for free. Users can also create group chats and make group calls.
Signal and Telegram are very different, but the similarities they have is that they collect a lot less data than Whatsapp and are not linked to "data mining machines" like Facebook, Mr Doffman said.
He said: “To my mind, most security professional professionals would recommend Signal. It’s non profit, it’s completely open source. It uses the same encryption Whatsapp uses.
“Until a few years ago, it was very clunky. What it’s done over the last few years, it’s become more user friendly. I prefer the interface of Signal, it’s nicer to use than Whatsapp.”
Mr Doffman said it is unlikely Signal could be acquired in the same way a private company is acquired, but the real question is how it can fund its ecosystem without touching users’ data.
Unlike Whatsapp, Signal does not offer to back up users’ messages, bypassing the issue of unencrypted messages being stored on a server.
And what about Telegram?
If you’re worried about security, leaving Whatsapp for Telegram is a mistake, Mr Doffman said.
Unlike Signal, Telegram is a platform for huge groups and has been used by protesters and dissonance movements.
It collects less data and it is partly open source, meaning there’s a lot of faith in Telegram, the cybersecurity expert explained.
But it is not encrypted end to end by default, unless users are sending “secret messages”.
Mr Doffman continued: “Its architecture though is client server. Your messages go to a Telegram service, then to recipients. But that is not secure. You can send encrypted messages, but that is from one phone to another phone. If someone’s worried about security, leaving Whatsapp to Telegram is a mistake.”