For those who may not have come across Signal before, it’s a messaging app that is similar to WhatsApp. It offers end to end encryption, it had self-destructing messages long before WhatsApp rolled them out this year, Signal group chats are user-based rather than server-based meaning messages never leave your phone. This also ensures that the server can’t tell if a message was generated in a group or in a private chat. On top of that, Signal is open source, which means anyone to examine its source code under a GPLv3 licence for clients and AGPLv3 for the server.
The biggest thing of all (in this case) is that Signal doesn’t have an entity like Facebook pulling its strings. You can communicate relatively securely and without having to worry about Big Brother siphoning off your information in order to send you targetted ads.
Lastly, Signal is what WhatsApp was before the Facebook takeover, and many who prefer a (relatively) private and secure messaging service have long since abandoned WhatsApp for Signal or Telegram.
As good as Signal is, the one thing it doesn’t have in Zim is a dedicated data bundle. This is a significant mark down for the app even though it has many upsides.
You should check out: What Makes Signal More Secure Than WhatsApp?