Does your VPN have open-source apps? Here's why you should care

A hand writing the words Open Source
(Image credit: Shutterstock)

What's the most important factor when you're judging a VPN? Speed, reliability, that it unblocks every streaming platform in the world? Maybe, but don't forget the apps. However it scores elsewhere, if the apps are short on features or difficult to use, that'll still trash your experience.

VPN providers understand this very well, and that's why most of them guard their apps closely. They keep them in-house, they're not used by other providers, and they're closed source - you can't see the source code.

This isn't a universal approach, though. Private Internet Access, ProtonVPN, Mullvad, AirVPN and others all have open-source VPN clients. Not only can developers look at the code to see how the apps work, other VPNs could even reuse it in their own apps.

While that sounds great, does it really matter to regular VPN users? Well, yes, we think it does. Here, we'll look at some of the benefits of open-source apps and why it might be worth considering when picking a provider.


Have you ever looked at a VPN provider's feature list and wondered how you can tell whether they're really delivering what they say?

Many VPNs promise they'll block malicious websites, for instance, or ads, or trackers. But how good are they at doing this? How can you test the feature? If this is some no-name free VPN app you've just found online, can you even be sure the feature exists at all, or that the provider has just made it up?

Choose a VPN which supports open source and it's a different story. Mullvad doesn't just claim to have ad and tracker blocking, its GitHub site (opens in new tab) shows how this works and even includes the lists of blocked domains for anyone to view.

Making a feature open source doesn't guarantee it's any good, of course. Still, just seeing Mullvad make the details available tells you it has some ad-blocking experience, and that the company has enough confidence in its solution to share it with the world.

Am open source headline from the ProtonVPN website

(Image credit: ProtonVPN)


We've peeked under the hood of a lot of VPNs, but it still surprises us to see just how really, really bad some VPN apps can be. 

If a provider is willing to open up its software to scrutiny, though, that deserves a lot of credit. Regular users won't even think of looking at the code, but a few experts will take an interest, and a company must be very sure of its quality to take that risk.

This confidence might not be justified, of course. Maybe the code isn't so great after all. Perhaps other developers will check it out and find some major bugs. Although that's not ideal, there's a positive side: going open source helps a VPN identify issues it's missed, giving it the chance to fix them more quickly.

How active is your VPN?

We think a quality VPN should regularly update its apps, optimizing the code, adding new features and fixing bugs. It's tricky to tell if a service lives up to these standards, though, because most give you no real details on what's changed in an update.

The open-source world is different because development happens in public, at sites like GitHub, and anyone can see what's going on.

You don't need any technical experience or knowledge to get some value from this. For an example, go take a look at ProtonVPN on GitHub (opens in new tab). This lists the various project names (android-app, win-app, ios-app and so on), and when they were last updated. If a VPN hasn't updated anything in months, that looks like a problem. But as we write, ProtonVPN has updated every project within the past 9 days - a great performance.

If you're the type of person who normally reads down 'What's New' lists and are curious what's to see exactly what's changed, click 'win-app' and the Commits link for an in-depth list of every recent addition.

The user interface of Eddie, AirVPN's open-source app

(Image credit: AirVPN)

Free tools

We've been focusing on the value of choosing a VPN with open-source technology, but that's not the whole story. Some providers make useful open-source tools which anyone can try, whatever service they're using.

For example, AirVPN's Eddie (opens in new tab) is a free and open source OpenVPN app. It's packed with features, has built-in Tor support and runs almost everywhere (Windows, Mac, Android, Linux and more.) And, best of all, you can easily use it with any other providers who support OpenVPN.

Although you'll mostly get the best results from using your own VPN's apps, Eddie could come in useful if, say, your VPN doesn't have an app for a particular platform, or you're trying to run it on old hardware (Eddie works on everything from Windows XP up, although using XP probably isn't a good idea for other security reasons).

Another Eddie plus is that there's a portable edition. You could save Eddie to a folder on a USB key, then plug it into another PC, and connect to your VPN without having to install the full app. Interested? It's open source, so you're free to download it and check it out for yourself.

Mike Williams
Lead security reviewer

Mike is a lead security reviewer at Future, where he stress-tests VPNs, antivirus and more to find out which services are sure to keep you safe, and which are best avoided. Mike began his career as a lead software developer in the engineering world, where his creations were used by big-name companies from Rolls Royce to British Nuclear Fuels and British Aerospace. The early PC viruses caught Mike's attention, and he developed an interest in analyzing malware, and learning the low-level technical details of how Windows and network security work under the hood.