iTunes Store

The iTunes Store, originally the iTunes Music Store, is a software-based online digital media store operated by Apple Inc. ... While most downloaded files initially included usage restrictions enforced by FairPlay, Apple's implementation of digital rights management (DRM), iTunes later initiated a shift into selling DRM-free music in most countries, marketed as iTunes Plus. ... As of June 2013, the iTunes Store possesses 575 million active user accounts, and serves over 315 million mobile devices, including iPods, iPhones and iPads. [iTunes Store. Wikipedia]