This free Mac tool lets me see which apps are quietly accessing the internet - and block them fast

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ZDNET's key takeaways

This app is perfect for controlling app internet access.

Firewally is free and installed from the Apple App Store.

This user-friendly app makes it easy to stay in control.

I'm always looking for ways to improve the security of my devices. Because my primary operating systems are Linux and MacOS, I don't have to worry all that much about security -- "all that much" being the operative phrase.

Here's one thing I always keep in mind: If a device is connected to a network, it's vulnerable, and it doesn't matter what OS is in charge. Therefore, I try to remain as diligent as possible about apps accessing the internet, my default firewall policies, and checking on data passing through apps.

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To help enhance MacOS security, I've found a simple-to-use app that handles all that work: Firewally. This free app (installed from the Apple App Store on MacOS devices) allows me to view real-time internet traffic for each app, set the default firewall policy for apps, and enable or disable individual app access to the network.

With Firewally, I not only have access to those features, but they're also very easy to use. In fact, you don't need much knowledge about how firewalls work to make this app work for you. You only have to decide whether an app should have internet access, whether you want the default policy for new apps to grant all apps internet access, whether an app should have to ask for internet access, or whether an app should be denied internet access.

The software is that simple to use. And because it's free, there's no reason not to give it a try.

Another feature found in Firewally is AI summaries for apps. (Because, why not?) The reason you might want those AI summaries is that they can show why an app might need internet access.

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For example, I use the locally installed Ollama for AI because it gives me the privacy I require. Ollama only needs to connect to a network to download LLMs and update them. Other than that, the AI tool can run entirely offline, which means, thanks to Firewally, I can disable its internet access until I need to download or update an LLM. With that feature, I can be certain I'm getting exactly the privacy I expect from the app.

How to get Firewally

Getting Firewally is easy. Open the App Store on your MacBook, iMac, or Mac Studio, search for firewall, locate the Firewally app, and click Get.

After the installation, you'll walk through an onboarding wizard that requires you to permit Firewally network access. Once you've done that step, you can enable the app to start at boot (which I recommend), and you're done.

After Firewally is installed and running, you'll find its icon in the top menu bar on your desktop.

Using Firewally

After you've installed Firewally, you won't find a traditional app to use. Instead, Firewally exists in the top menu bar. Locate the Firewally icon (a small shield) and click it to open the pop-up.

The default view for the Firewally pop-up is the Hourly tab, which shows how much traffic an app has generated in the past hour.

One of the first things I would recommend you do is switch the default policy from Pass to Ask by clicking the dropdown near the top-right corner. When you switch to Ask, any new application will need your permission to access the internet, which I find to be the safer option. If you stick with Pass, all new apps will automatically have internet access.

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Next, you can scroll through all currently running apps and do the following:

Hover your cursor over the AI icon to view an app summary.

Hover your cursor over the small basketball-looking icon to view real-time network traffic statistics.

Click to disable (or enable) an app's internet access.

Switch to the Real Time tab to view only the apps that are currently using the internet.

Switch to the Today tab to view all apps that have accessed the internet today.

Access the Firewally settings (by clicking the gear icon).

There really isn't much in the way of Settings for the app. You can disable AI summaries and set Firewally to launch at system start, and not much else.

Beyond the default policy, the most important aspect of Firewally is the ability to disable an app's internet access on the fly. For this feature, all you have to do is locate the app and move the On/Off slider to Off. As I mentioned earlier, I disable Ollama's internet access until I need to download or update an LLM; otherwise, it remains off.

Be cautious about which apps you disconnect from the internet. An obvious example would be your web browser. Disable its internet access, and the app won't function. If, on the other hand, you find an app listed that shouldn't have internet access, be safe and disable it.

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I've been using Firewally for a while now and have found it indispensable. I like to control whether apps have internet access, and Firewally makes that step easy.