Best Messaging Apps for Privacy

Callum Tennent
By Callum TennentUpdated

The messaging app market has exploded over the last 5 years. Armed with a smartphone and a data connection, you can contact practically anyone in the world instantly, and for free. But despite their extended features, which ones are the most private and secure?

Best Messaging App for Privacy & More

The first SMS was sent in 1992, although it wasn’t sent from a phone. Neil Papworth, a developer, used his PC to send a text message to a Vodafone employee. 25 years on, the messaging market has exploded, and the internet has reduced costs and broadened choice.

Whether you want to group chat, video call, or exchange animated GIFs, there’s a free app that will do the job for you.

So which app should you use as your primary messaging tool to keep your conversations private and secure?

In truth, it’s difficult to pick just one. As messaging apps evolve, they are increasingly catering to their own niche demographics. What works for a family sharing holiday snaps may not be adequate for a journalist working on breaking news.

Privacy & Security

How private is a private chat? Could a hacker intercept your messages and read them?

Users are very conscious of the risks, and as a result, messaging apps are taking security more seriously.

Security can be difficult to understand, since there are different factors to take into account. We’ve looked at the most popular messaging apps and how they fare in terms of encryption:

App End to end encryption Protocol Open source Parent company
Facebook Messenger Yes (must be switched on) Signal / Open Whisper Systems No Facebook
Signal Yes Signal / Open Whisper Systems Yes Signal Digital
Skype No Skype No Microsoft
SMS No None N/A N/A
Telegram Yes (must be switched on) MTProto No Telegram Messenger
Viber Yes Undisclosed (proprietary) No Rakuten
WhatsApp Yes Signal / Open Whisper Systems No Facebook

All of the apps, except SMS and Skype, offer end-to-end encryption.

The Signal Protocol used by Facebook Messenger, WhatsApp, and Signal is widely regarded to be one of the best choices. But the protocol is not the end of the story. Telegram and Facebook Messenger don’t enable encryption by default. You need to manually switch on the secret chat feature to use it.

Encryption is important but for super sensitive communication, go open source.

What about open source? Here’s why that matters:

  • If a messaging app is open source, it means that the code can be independently inspected. That ensures that the app really is private, and it’s not storing your data in secret.
  • Closed source messaging apps can still be secure, but nobody has had the chance to look at the code to verify that claim.

For highly sensitive conversations, you should use an open source app that’s been rigorously examined to ensure that its security is up to scratch.

Winner: Signal was recommended by Edward Snowden and Laura Poitras, the journalist that broke his leaks about government surveillance. It uses a respected protocol, it’s open source, and it isn’t owned by a huge corporation.

Other Features

While Signal is our recommended encrypted messaging app, we thought we’d also look at other aspects of these apps that may be of interest.

Most of these apps cover the basics well. All do text chat, along with SMS, and all of them can handle picture messages and file transfers, although Signal’s file size limit is a tiny 300kb. That’s because it tries to comply with the ‘traditional’ limits of MMS messaging.

All of the apps, except SMS, offer true group chat. In order words, you can have a conversation where everyone can see all replies within the group.

Modern messaging apps are packed with features. Pick what’s most important to you.

Viber and WhatsApp offer push-to-talk; Facebook Messenger and Viber supports sticker messages. Viber goes one stage further with an animated GIF chooser that’s integrated right into the app.

When it comes to calling, we begin to see key differences in each of the apps:

  • Telegram doesn’t offer voice or video calling
  • Signal has only recently added both to its app
  • WhatsApp and Viber do a reasonable job, but quality can be lacking, and neither comes close to the slick experience within Skype
  • Facebook Messenger theoretically allows you to video call 50 people at once, although you’d have to have a pretty large phone to be able to actually see them.

The final thing to consider is backups (and, on a related note, migration to a new handset). Again, we see some big differences which we can summarize by looking at WhatsApp and Signal:

  • WhatsApp lets you back up messages to the cloud for easy migration, but if you do this, you are placing them on a third party server. In theory, that’s a privacy risk.
  • Signal doesn’t offer any backups. The upside is that you won’t need to worry about the risk of storing messages elsewhere, but this also makes it impossible to migrate Signal messages when you upgrade your device.

Winner: Viber balances a broad range of features with a solid focus on the essentials. But this is a close-run thing. There will always be one app that is better at a key feature than all of its competitors. Signal, for example, is poor on flexibility but does security very well.


Most mobile operators are moving towards low-cost or free SMS texting, so messaging apps have to be free – or very cheap – in order to stay competitive.

Here’s a run-down of the current position:

  • WhatsApp dropped its fee in 2016 and is now totally free.
  • Viber and Facebook Messenger are ad-supported.
  • Telegram is free to use.
  • Signal is supported by grants and donations.
  • Skype is free.

There are paid services in most of these apps, but for basic usage, you won’t pay a cent. However:

  • Both WhatsApp and Facebook Messenger share data with advertisers, and this sharing could take place across all Facebook-owned apps.
  • Facebook Messenger is already offering businesses the chance to run chat bots. These aren’t advertising per se, but they are technically funding the service.

Ease of Use

With any app, ease of use can be subjective, and it’s influenced by a range of factors. Something that is easy to accomplish on a modern handset could be tough on an older smartphone.

It also depends which features you want to use, since all of the apps do text chat very well. So on that basis, there isn’t much between them.

SMS is technically the easiest app to use for pure text chatting. But doing anything more complicated, like sending contacts or MMS, can result in an unpredictable experience. Telegram and Signal are also simple in that their functionality is limited, which makes the interface clean.

Arguably, the most complicated apps in the list are the ones with the most features: Skype, WhatsApp, and Viber.

More features means an app is harder to use: from Signal’s simplicity to Skype’s complexity.

Skype’s interface has changed little over the years, which means it can be unintuitive. Getting people into a group call is particularly complicated if you haven’t tried it before, and contacting users on the separate Skype for Business product (formerly Lync) is more irksome than it needs to be.

Facebook Messenger benefits from smooth integration with the Facebook interface. There are various ways of using it on desktop, so most users will have had some exposure to it before they fire up the app for the first time. This consistency of the experience means that most people will find Facebook Messenger easy to use.

Winner: Facebook Messenger


Almost all of the apps we’re looking at publish adoption figures, so we can see at a glance which ones are favored globally. Unsurprisingly, some of the newest messenger apps are the ones still gaining traction.

App Adoption
Facebook Messenger ~1 billion
Signal 3.62 million
Skype 74 million
SMS 4.2 billion
Telegram 49 million
Viber 800 million
WhatsApp 1 billion

The only app that we couldn’t find figures for is Signal. It only really received a boost when Edward Snowden endorsed it, and its lack of full picture messaging is likely to be a reason why it hasn’t gained ground faster.

Signal is only just starting to gain popularity now since its endorsement by Edward Snowden.

The app has been downloaded up to 5 million times on the Google Play store, which is our best indicator of adoption. But it’s important to remember that other app stores don’t publish this kind of data, so the total can’t be determined. Apptopia estimates that the figure is around 3.62 million downloads overall.

As Signal has been banned in some countries, Telegram has picked up the slack. Apptopia says that it has more than 49 million users.

Despite being one of the most mature apps in the list, Skype has a relatively modest user base of around 74 million people. Facebook Messenger easily dwarfs this figure with more than 105 million users in the US alone. In total, analysis suggests around 1 billion people use it.

Now we’re in the league of the real big hitters. Viber hovers around 800 million users currently. WhatsApp sits at a cool 1 billion users, making it the world’s most popular messaging app, in the pure sense of the word.

Research suggests that more than 4.2 billion people still use SMS messaging, and collectively, they send 560 billion texts each month. That is a very sobering stat and the more people stop using SMS, particularly for sensitive texts, the better.