At the most basic level, there are just a few ways that outsiders can walk away with information from your Mac, whether it be usernames and passwords, personal files, email or contact information, or anything else you’d rather keep to yourself than share with others.
First, someone could steal your Mac. Second, someone could use your Mac while you’re away. Third, someone could try to hack into your Mac (which happens 24/7 if your Mac is connected to the internet), or Fourth, apps on your Mac phone home; whereby phone home means connect from your Mac to a server somewhere else on planet earth and send information.
Most Mac users have less control over what goes on in their Macs than they think because nearly every application you use– and many apps you do not use– phone home at all hours of the day.
Some of that phone home exercise comes from you, and some of it from Apple. For example, if you use Mail, then the Mail app must connect with email servers. If you use Safari to browse the interwebs, then Safari connects to website servers. Those third party applications that tell you they need to be updated? They phoned home to the developer to check. Apple itself has all kinds of background applications that phone home to various Apple servers.
Open the Applications folder, scroll down to the Utilities folder, then open Activity Monitor app. It’s likely you’ll see Mail and Safari and other Mac apps running within the list, but there are dozens of background processes and other apps also running, and most of us don’t know what they do.
Many of them phone home for various and sundry reasons. How can you find out which ones and where and why they phone home? Install Little Snitch. This superbly crafted Mac app acts somewhat like a reverse firewall to stop outbound traffic from your Mac to who knows where– all of it, but you control which apps can connect and where.
As soon as you’re connected to the Internet, applications can potentially send whatever they want to wherever they want. Most often they do this to your benefit. But sometimes, like in case of tracking software, trojans or other malware, they don’t. But you don’t notice anything, because all of this happens invisibly under the hood.
Little Snitch stops all that with a little popup window with options to control the outbound connection.
You’ll seen plenty of such popup warnings when you first start up Little Snitch, but there is a built-in Silent Mode which helps to reduce the notifications to a more manageable amount.
After all, we’re not too worried about Calendar, Safari, Mail, iTunes, and other Apple or name-brand applications phoning home, right?
Sounds good so far, right?
Little Snitch lets you know which apps are trying to connect from your Mac to another server somewhere else on planet earth. Most such connections are innocuous, including the need for apps to check if there are recent updates, or to share information with counterparts on other Macs, iPhone, or iPad.
Here’s the problem. Many of those applications connect to outside servers from your Mac and we don’t know where those connections are made, why they’re being made, or what kind of data is being transferred or shared with those remote servers.
Little Snitch has a very cool and highly visual Network Monitor which helps.
Yeah, that’s right. Little Snitch can track where the connections go from your Mac. And, yes, that’s right, it can be scary. For the most part, I’m rather careful about which websites I visit, which apps I download and install on the many Mincey Macs, and I’m still shocked at apps that make connections to China and Russia, not to mention elsewhere.
What Little Snitch does not do and probably cannot do is determine what information is being shared to remote servers from your Mac. That remains app independent, but at least you get an idea of what’s going on.
Yes, it is surprising and a bit terrifying to know how many applications need to connect to servers from your Mac, regardless of the reason.