Signal: The Free Private SMS App We Trust on Android

There are plenty of apps that promise privacy, but most of them ask you to take their word for it. Signal is different because the encryption is on by default, the code is open for anyone to inspect, and the nonprofit behind it does not run on advertising. When we send a message to another Signal user, it is end to end encrypted, which means not even Signal can read it.

One thing to set straight early. Signal used to handle your regular carrier SMS texts directly, but that feature was removed a while back, so today it focuses on its own encrypted messages sent over the internet. We still think of it as the best private replacement for texting because most of the people we message regularly are happy to install it once they see how clean it is. If you need a few quick comparisons across the category, our roundup of the best messaging apps for Android is a good place to start.

Getting started took us under five minutes. Open the Play Store, search for Signal, and tap Install. When you first launch it, the app asks for your phone number and sends a verification code by text to confirm it is really you. Pop that code in and you are nearly done.

Next it offers to set a PIN. We strongly suggest doing this. The PIN protects your account and helps you recover your profile and settings if you switch phones later. You can also add a profile name and photo, though neither is required. The last step is letting Signal find which of your contacts already use it, which it does in a privacy preserving way rather than uploading your whole address book in plain form. Once that finishes, anyone in your contacts who already has Signal shows up ready to message.

If you are coming from another phone or app, give the people you text most a heads up that you are moving over. In our experience, the switch sticks much faster when a couple of close contacts join you in the first day.

Day to day, Signal feels like any modern messenger, just calmer. Texts, photos, voice notes, group chats, and high quality voice and video calls all work the way you expect, and every one of them is encrypted. The feature we lean on most is disappearing messages. You can set a timer on any conversation so messages delete themselves after a set time, from a few seconds to four weeks, which is handy for anything sensitive you would rather not leave sitting on the screen.

We also like the small touches. View once photos vanish after the recipient opens them. You can edit a message shortly after sending to fix a typo. Stickers and reactions keep group chats fun without feeling bloated. And the notification privacy settings let you hide message content from your lock screen, so a glance at your phone on a desk does not reveal who said what.

If personalising your chats matters to you, it is worth seeing how Signal stacks up against the more playful options in our look at customizable messaging apps.

This is where Signal earns its reputation. The permissions it requests all map to features you would expect. It asks for Contacts so it can show you which friends are reachable. It asks for Camera and Microphone for photos, voice notes, and calls. It asks for Notifications so messages actually reach you. That is roughly it, and you can decline any of them and still send text messages.

What we appreciate is what is missing. There is no constant location tracking, no advertising identifier harvesting, and no quiet syncing of your data to third parties. The app collects almost nothing about you. The one piece of metadata Signal needs to create your account is your phone number, which is the main trade off and the thing privacy purists grumble about most.

No app is perfect, and Signal has a couple of honest limits. The biggest is the network effect. Signal only protects a conversation when both people use it, so if your family still texts over standard SMS, those messages are not encrypted and you may end up nudging people to install yet another app. For some circles that is an easy sell, for others it is friction.

The phone number requirement is the other sticking point. You need a real number to sign up, so it is not the tool for fully anonymous contact. There is a usernames feature that lets you chat without handing out your number, which softens this, but the account itself is still tied to a number. Finally, because so much is encrypted and stored only on your device, losing your phone without a backup or PIN can mean losing message history. Set that PIN, enable backups, and you sidestep the worst of it.

If you cannot get your contacts to switch, you have a few sensible options. WhatsApp uses the same underlying encryption protocol as Signal and almost everyone already has it, though it is owned by Meta and collects more metadata. For a number free, decentralised approach, Session and similar apps drop the phone requirement entirely, at the cost of a smaller user base.

You can also keep your phone's built in messaging app for plain SMS and reserve Signal for the conversations that matter, which is exactly how we run things. To weigh more contenders side by side, our guide to the top free messaging apps for Android breaks down who each one suits, and the wider communication apps hub covers calling, caller ID, and recording tools if you want to round out your setup.