Gmail and Facebook are first and third most popular iOS apps collecting personal information

So far there has still been no Facebook 'adpocalypse'

In context: Apple recently made some significant changes in how App Store developers collect data from users. It implemented its App Store Transparency labels last December and its iOS 14 App Tracking Transparency framework on April 26.

As we have previously reported, as of May 8, iOS 14 users have said "no" to apps asking permission to collect their data 96 percent of the time. It's not that surprising, considering users have never before had more control over their personal information on any platform.

On Thursday, app intelligence firm 42matters revealed stats on Apple's App Store policies and its transparency framework. The company has APIs and other tools it uses to query specific data from the App Store. Some are pretty telling.

Apple has four general categories for its app privacy labels—Data Used to Track You, Data Linked to You, Data Not Linked to You, and Data Not Collected. Data can fall into more than one category.

Data Used to Track You is cross-app data gathered by the app or a third party, such as your browsing history. This is primarily used to target ads of interest. Of the 1,816,392 iOS apps currently available on the App Store, 99,282 have this label. Twitter is the most popular app under this label, with more than 8.8 million downloads.

Data Linked to You is any of your personally identifiable information (PII) regardless of whether it is being used for advertising or not. For example, data entered into an app to set up an account falls into this category. There are 191,471 apps with this label. So nearly double the apps that track you are also collecting PII. Unsurprisingly, Google's Gmail app tops the list of apps collecting PII, with Facebook's app running a close third.

Data Not Linked to You is any information that an app might collect that is not PII. For instance, geolocation or browsing history. Apps with this label are the most abundant at 218,294. A game called Subway Surfers is the most popular app in this category.

Lastly, Data Not Collected is applied to any apps that list at least a single data type, i.e., email address, as not collected. There are 215,662 apps with this label. The most popular app that does not collect data is FNF Ultimate MOD Game, a rhythm game that you probably have never heard of, even though players have downloaded it over 3.7 million times.

What can we learn from this? Facebook has been Apple's most vocal critic on its new privacy rules, and now we know why. By download, Facebook only trails slightly behind Google for apps that collect personally identifiable information—data they both use to build user profiles for advertisers. It also shows that a majority of the 1.8 million apps in the App Store have not even adopted the the new labeling system. A lot of these are likely abandonware, but Google has been putting off update to avoid the system. Other developers are probably following that lead.

It's going to be interesting to see how this changes the way Big Data firms like Facebook and Google operate on iOS now that users can tell them, "Leave my data alone." Facebook has already foreshadowed how it's going to handle things by the WhatsApp example—opt-out, lose your account, or at least the app's functionality.

Image credit: 42matters