Twitter is starting a new program called App Graph that tracks all of the other apps people have on their phones. You might be wondering why Twitter cares if you're a Candy Crush fiend or if you also use Instagram. It's because Twitter follows the ABT school of sales: Always Be Targetin'.
Tracking the other apps on your phone helps Twitter build a profile on you, which helps it figure out what kind of shit you're most likely to impulse purchase after seeing a mobile ad.
Twitter didn't have to update its permissions to do this, but it is making a concession to privacy worries by showing people a prompt that lets them know this new feature is running. It's opt-out, so if you're not down with Twitter peeking at your other apps, you have to manually change your settings:
This isn't a groundbreaking revelation by any stretch. Compared to Facebook tracking browser histories for data, it's relatively tame. But it is a reminder that the apps you download on your phone can collect information beyond what you do while actively using them. And that apps are going to use the data they siphon to aggressively market things to you. [Recode]