Lockdown brings open source firewall to iOS | Cult of Mac

Lockdown brings open source firewall to iOS


Lockdown secures your iPhone with a firewall.
Lockdown secures your iPhone with a firewall.
Photo: Charlie Sorrel/Cult of Mac

Lockdown Apps is a new firewall app for iOS. Like Guardian Firewall, which we covered last month, Lockdown uses iOS’ VPN framework to intercept all incoming and outgoing network traffic, and allows you to block connections to any address.

Unlike Guardian Firewall, Lockdown operates entirely on your device. It is also open source.

Why iOS needs a firewall

The new Lockdown Apps iOS firewall locks stuff down.
Lockdown locks stuff down.
Photo: Lockdown

The Mac has long had a user-configurable firewall, but on iOS the only built-in security tool we have is Safari’s content blocker. And that only works for web pages.

Lockdown and Guardian Firewall aim to change that. Lockdown, from developer Confirmed, comes with a few rules preconfigured, but it’s up to you to add new addresses to the list. Anything you add will be blocked, both on the web and inside apps. Safari’s content blockers can block the Facebook website, and Facebook cookies, but Lockdown will stop any app — even Facebook’s own apps — from connecting to facebook.com.

Guardian Firewall

Guardian Firewall does all the hard work for you.
Guardian Firewall does all the hard work for you.
Photo: Guardian Firewall

The Guardian Firewall app, on the other hand, routes all your internet data through its own servers, and strips out any dodgy traffic. It also blocks connections it deems malicious or that compromise your privacy. This approach is less secure, or at least harder to be sure about, because you have to trust the folks behind Guardian Firewall with all your data. But is it also much more effective, as you don’t have to manually block anything. And the developers behind the service seem trustworthy in my limited checking.

The Guardian Firewall developers also decompile and examine app store apps to find out what kinds of data they are stealing/sharing, if any. According to the devs:

This capability allows us to monitor changes in real time as trackers are added, updated, and removed from apps. We can easily find out what types of data are sent to external servers, and that is why each alert in the app is able to describe what we prevented from going out by blocking the connection.

On Lockdown

Lockdown’s on-device approach is more transparent to you, the user. You can check out the app’s source code on Github. And if you have a developer account, you can build it yourself and install on your devices. (I wonder if there’s a way to check that the version available in the App Store is built from the same source. If you know about this, let me know on Twitter or in the comments on this post.)

The takeaway, though, is that there are now two legit firewall apps for iOS. You will find both of them in the App Store (Guardian Firewall will be available July 31). And both use an approved method (VPN) to do their job. I’d rather iOS came with a built-in firewall, but this is a huge step in the right direction.

Lockdown Apps

Price: Free

Download: Lockdown Apps from the App Store (iOS)


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