Twitter has just added a section to its security & privacy terms that explains how the company is about the start “collecting and occasionally updating the list of apps installed on your mobile device”.

Re/code first spotted the updated page, which explains Twitter’s ‘App Graph’ and what it means for you.

In short, Twitter is occasionally checking in on which apps you have downloaded – but that’s as far as it goes. Twitter assures users that “we are only collecting the list of applications you have installed … we are not collecting any data within the applications.”

Why would Twitter want to do this? Well, ads first and foremost. Generically, Twitter’s rationale for the app-tracking is to “help build a more tailored experience for you on Twitter”. More specifically, that means “showing you more relevant promoted content”.

Twitter also says this will help them to add more interesting content to your timeline. You may have noticed recently that Twitter has been messing with your timeline a bit, showing tweets and other stories from and about accounts you don’t follow.

If your first thought is something along the lines of oh hell no – don’t worry – it’s easy to turn off. All you have to do is find the “tailor Twitter based on my apps” option in your settings and shut it down. For iOS users, it’s located under Privacy inside Settings. For Android users, it’s located inside the Other section inside Settings.

But here’s the thing – Twitter’s probably not tracking your apps yet. Here’s how it will go down:

We will notify you about this feature being turned on for your account by showing a prompt letting you know that to help tailor your experience, Twitter uses the apps on your device. Until you see this prompt, this setting is turned off and we are not collecting a list of your apps.

So, until you see the warning, there’s nothing for you to do.

Opt-out data tracking is probably one of the least-popular things on the planet – running close behind root canals and Yoko Ono Christmas covers. We’ll see how this goes over the next few days/weeks – but I’m betting there will be some backlash.

Image via Jason Howie, Flickr Creative Commons