Free, privacy-focused messenger
Signal is a messaging app, focused on security and privacy issues. In the sea of existing communication applications, Signal is irreplaceable for those who appreciate strong, open-source, end-to-end encryption. Your Mac is yet another spot, where you can access this star software.
Security and privacy
Messaging apps have become an inseparable part of our daily life. However, do you know how much data the corporations behind those programs collect about you? It's metadata that might contain anything from your personal and contact information, phone contacts, and even your files.
To some degree, all messaging applications collect and store the mentioned data in the corporate servers. On the 'most secure and private' end of the spectrum is Signal. The company only has your account creation and 'last used' dates. Thus, it can't sell or disclose any information to third parties (including governments).
All your messages stay on your device, making the conversations inaccessible from any other location. You can ensure that a conversation or a call is safe by verifying that the code on your screen matches the one on the recipient's end. Brute-force hacking is borderline impossible. Moreover, Signal's code-base is open-source - anybody can check its security and authenticity.
Why use Signal over other messaging apps?
While the security aspect is the most obvious reason to switch to Signal, you should consider the tradeoff and features that you'll need to forego. Other applications have more functionality such as Viber, which lets you move an ongoing conversation from one device to another.
Another option would be Telegram as it generously offers file transfers of up to 2GB. Then, there is the ever-controversial WhatsApp, with its support for stickers, group chats, and other social-focused features.
At the end of the day, though, while Signal lacks some creature comforts that you have come to expect from using other messaging apps, it more than makes up for it by replacing features with strict and better security tools protocols than any other app.
Private, secure mobile messaging
Signal is the clear winner among all the messaging apps if your main priority is wanting to keep your messages out of servers and your data away from prying eyes. Mac users can enjoy the software without any complications, and with the added benefit of device-stored communication.