T-Mobile’s advertising business is offering a new way for marketers to pry into your app-using habits. Ad Exchanger reports that the un-carrier’s new program is called App Insights, and it’s now fully operational after spending a year in beta. The program allows third-party marketers to buy T-Mobile customer data and centers around a key piece of information that it has unique access to: what apps you use.
Customer data is anonymized, and it’s pooled together with others of…