App Developers Can Stalk You Around the Web if You Uninstall Their App

We’ve all gotten used to the fact that installing an app on a smartphone means the developers will get at least some information about us. Both Android and iOS include controls to block app permissions, and you can always remove an app if you think it’s being too nosey. As it turns out, uninstalling an app might just make a developer more interested in what you’re doing. A new report explores how developers track the users who uninstall their apps — you might prefer to call it “stalking.”

These so-called “uninstall tracking” tools are offered by companies like MoEngage, Localytics, and CleverTap. Big companies like T-Mobile and Spotify use these services to figure out when people uninstall their apps, but they’re not alone. Plenty of smaller developers are also following uninstallations because it’s a clear signal that someone could be a good target for advertising.

Think back, and you might recall being the target of uninstall tracking. If you’ve ever seen a plethora of ads for a particular app or service after uninstalling that app from your phone, that developer is probably using uninstall tracking to try and win you back. This technique uses a perfectly legitimate feature of mobile operating systems: push notifications. Yes, the same functionality that brings you new Tweets and emails could also help developers stalk you.

Both iOS and Android allow developers to reach out to your phone when you have their app installed. If the app is present, the phone replies and receives data. However, the phone is silent if the app is no longer installed. Uninstall tracking notes this as a newly lost user, giving the developer a chance to pitch woo at you. This is where things get stalker-ish.

Every mobile device has a unique advertising ID, which companies use to target ads unless you disable this feature in your account settings. Uninstall tracking uses that ID to follow you around the web and hit you with ads, imploring you to reinstall the app. Companies could use uninstall tracking to find out why people uninstall apps and make improvements, but more often than not, they appear to just go after users with ads.

This behavior is technically against the rules imposed by both Apple and Google. Developers aren’t allowed to use push notifications to send ads or generate an advertising database, but it’s unclear if Google or Apple could feasibly to enforce that. For the time being, you should opt out of ad personalization features in your Google or Apple iAds account if this bothers you.

Now read: No, Google Didn’t Just Sneak DRM Into All Android Apps, Apple App Store Antritrust Case Is Headed to the Supreme Court, and Google’s Voice Access App Lets You Control Your Phone Entirely Hands-Free