"Stalker apps" on Facebook—apps that claim to show you who's been looking at your profile—are not real. We're telling you that up front because it's not quite obvious to the people who use Facebook, including many Ars readers (we know because we see the posts you guys make there).

Yes, it's incredibly tempting to believe that you will be able to see each time your high school sweetheart cruises your photos, or anytime your crazy housemate does a relationship status check on you without them ever knowing that you're watching them back. But alas, it is impossible.

The apps that have made their way around the social network lately have been a mixture of phishing scams and twists of the truth. We've decided it was time to explain why you shouldn't believe anyone who claims you can surreptitiously find out who's been Facebook stalking you

How this madness got started

For those of you who remember MySpace (what, you mean it still exists?), you probably remember when all this started. Back in the mid-2000s, word started spreading that MySpace users could embed some code into parts of their profiles that would allow them to get reports on which other MySpace users were checking them out and when.

Because MySpace allowed its users to put practically any kind of HTML, CSS, JavaScript, iFrames, and other code on their profile pages, this was really easy to do without other users knowing anything was amiss—and it worked. And trust me, the reports were boring. Wow, my friend Jody showed up on my profile for 5 minutes before making a post saying we should go out soon? Fascinating stuff.

That tool and its numerous spinoffs eventually broke as time went on, while others sprung up in their place. That's around the time that malware and spam started getting big on MySpace and Facebook started becoming more popular. People started migrating away to the "cleaner" social network with stricter privacy controls and less visual vomit.

It turns out that those users may have wanted stricter limitations on how others could modify their profiles, but they still wanted to be able to see who has been looking at their own profiles. Enter the era of the Facebook stalker apps.

Facebook's stalker trackers

With the introduction of Facebook apps—Web widgets that can be embedded into various parts of your profile—some of that aforementioned visual vomit returned, but in a more respectable-looking way. As we've learned, not all Facebook apps do good things. Over the past couple years, a plethora of apps have popped up claiming to provide users with info about who's looking at their photos, who's perusing their wall posts, and in general, who's "stalking" them. All of these are bogus.

In fact, it's not even possible for a Facebook app to gather that kind of data under Facebook's current terms. "Facebook does not provide applications or groups with the technical means to allow people to track profile views or see statistics on how often a particular piece of content has been viewed and by whom," Facebook wrote in response to a question about whether stalker apps really exist. "If an application claims to provide this functionality, please report the application."

So what, exactly, do these apps that claim to track your stalkers do? The recent swath of stalker apps (some of which don't even exist anymore at the time of publication, so it's hard to pin them down) tended to do one of two things: either their explicit goal was to gain access to your profile information in order to sell it or hijack your account, or they technically didn't show you your "stalkers."

A recent app called Stalker Checker, for example, ended up showing you the users who were the most active on your Facebook account. So, if you had a friend who was constantly commenting on your wall posts and leaving "Likes" all over your images, he or she would show up on the Stalker Checker. If you had an ex-boyfriend who was visiting your page every day without leaving a trace, however, he would not show up on the Stalker Checker.

Other spinoffs work with the same concept—trying to pinpoint who shows the most activity on your profile—but sometimes they simply list friends of yours randomly just to have something to show. Of course, this is not exactly the most effective tool if it can only tell you about your "stalkers" based on who's making themselves the most conspicuous to you. And because Facebook won't give developers a way to see that info otherwise, trying to install an app that claims to see your stalkers is an exercise in futility.

An unfriend tracker, however...

A slight spinoff from the stalker apps is the concept of the "unfriend tracker"—the idea that you'll be able to see immediately when someone on Facebook has decided that you're no longer e-friends. You can't get an unfriend tracker through Facebook's collection of apps, but you can install a script on your favorite browser (usually using Greasemonkey, GreaseKit, SIMBL, or NinjaKit) in order to monitor those changes on your profile.

Let us just tell you up front though: it's not worth the trouble. Do you really want to exist in a world where you are dependent upon browser script to tell you that a "friend" of yours has severed your relationship via Facebook? Take some personal advice from us to you: the mental anguish that comes with analyzing how or why such a thing could happen isn't valuable at all. If your "friend" doesn't have the decency to tell you directly why you're no longer friends, don't waste valuable brain (or computer) cycles trying to figure it out.

Don't do it

Considering how much information the normal Facebook apps can legitimately collect from your profile, it's wise to avoid apps that don't do what they claim (after all, if you can't trust a developer to market the app to you honestly, you can't trust him or her to use your data properly either). Don't fall for apps that pretend to tell you who's looking at your profile—they're not real!—and give into temptation with the unfriend scripts either. You're better off without them.