Signal: A Secure, Open Source Messaging App

Brief: Signal is a secure open-source messaging app for smartphones. It also offers a standalone desktop app for Linux, Windows, and macOS. Here, we take a look at its features and usability.

Signal is an Excellent Alternative to WhatsApp (and Telegram) for Privacy Concerned People

Signal Shot
Signal App On Linux

Signal is an open source application with a keen focus on privacy. It is recommended by privacy advocates like Edward Snowden.

It may not have as many features as Telegram or WhatsApp – but if you want to enhance your privacy while having a conversation, this is a solid open-source solution.

You can install it on your smartphone (iOS/Android) and it is also available for Linux, Windows, and macOS.

Features of Signal Messenger

Note: Some of the features are specific/exclusive to smartphones. You may not observe all the features mentioned in the desktop app.

Also note that, for now, Signal requires a phone number to register. If you do not want to expose your private phone number, you can use Google Voice or similar services.

As I already mentioned, this is tailored to enhance your privacy. So, the user experience may not be the “best” you’ve ever seen. But, privacy/security-wise, I think it is a good option to have.

Signal Phone
Signal Features

Disappearing Messages

You can set a timer for messages in a conversation – so that it will be automatically deleted as per the timer.

Essentially, anyone in the conversation can activate this feature. So, you control if the messages should stay in a conversation or disappear.

Use it As Default SMS App

If you want to utilize an open-source app for all your SMSs, you can simply go to Signal’s app settings and set it as the default for SMS and MMS.

Screen Security

There’s a neat feature to block screenshots in-app, “Screen Security”.

If you enable it, you won’t be able to take a screenshot of any conversation in the app. You can find the option to enable or disable it from the app settings.

It may not be useful to everyone – but you can try it out.

Safety Number

If you want to verify the security of your encryption with a friend, you can simply tap on the profile and scroll down to find “View Safety Number”.

You can either scan it to verify or simply take a look at it to mark it verified.

Locked Messages

If you protect the app with a lock (pin/fingerprint), even if your device has been unlocked, you won’t be able to see the messages on your notifications.

So, when you get a notification while Signal is locked, you will notice the content of the notification as “Locked Message” – which is a plus for privacy-oriented users.

Other Features

Signal Shot 1

As you would expect in a messaging app – you get a couple of stickers to utilize and you can also create a group if you want.

However, you won’t have the ability to moderate your group – you can just add members and change the profile picture.

In addition to this, Signal also supports biometric security for its app.

Installing Signal on Ubuntu/Linux

Unfortunately, you don’t get a .deb or .AppImage to install it on your Linux distro. But you can still install Signal on Ubuntu using their repository.

Here’s what you have to type in the terminal:

curl -s | sudo apt-key add -
echo "deb [arch=amd64] xenial main" | sudo tee -a /etc/apt/sources.list.d/signal-xenial.list
sudo apt update && sudo apt install signal-desktop

Simply copy-paste the commands one by one in the terminal and you should be good to go.

My Thoughts On Signal

I’ve been using Signal for a few years now and it has improved with what it offers. However, I still feel that the user experience can be improved.

Privacy-wise, it is definitely a good alternative to what we already have (in my opinion). You can give it a try and see how well it works for your usage.

You can also take a look at their GitHub page for the latest developments and beta releases if you want to try them out.

Signal app may not be a popular messaging app when compared to WhatsApp or even Telegram on Linux. But, you can try it for yourself and encourage your friends to use an open-source messaging app.

Have you tried it yet? Let me know what you think about the ‘Signal’ app in the comments below.

About the author
Ankush Das

Ankush Das

A passionate technophile who also happens to be a Computer Science graduate. You will usually see cats dancing to the beautiful tunes sung by him.

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