ITunes

Music library

iTunes features a music library. Each track has attributes, called metadata, that can be edited by the user, including changing the name of the artist, album, and genre, year of release, artwork, among other additional settings. The software supports importing digital audio tracks that can then be transferred to iOS devices, as well as supporting ripping content from CDs. iTunes supports WAV, AIFF, Apple Lossless, AAC, and MP3 audio formats. It uses the Gracenote music database to provide track name listings for audio CDs. When users rip content from a CD, iTunes attempts to match songs to the Gracenote service. For self-published CDs, or those from obscure record labels, iTunes would normally only list tracks as numbered entries ("Track 1" and "Track 2") on an unnamed album by an unknown artist, requiring manual input of data.

File metadata is displayed in users' libraries in columns, including album, artist, genre, composer, and more. Users can enable or disable different columns, as well as change view settings.

Special playlists

Introduced in 2004, "Party Shuffle" selected tracks to play randomly from the library, though users could press a button to skip a song and go to the next in the list. The feature was later renamed "iTunes DJ", before being discontinued altogether, replaced by a simpler "Up Next" feature that notably lost some of "iTunes DJ"'s functionality.

Introduced in iTunes 8 in 2008, "Genius" can automatically generate a playlist of songs from the user's library that "go great together". "Genius" transmits information about the user's library to Apple anonymously, and evolves over time to enhance its recommendation system. It can also suggest purchases to fill out "holes" in the library. The feature was updated with iTunes 9 in 2009 to offer "Genius Mixes", which generated playlists based on specific music genres.

"Smart playlists" are a set of playlists that can be set to automatically filter the library based on a customized list of selection criteria, much like a database query. Multiple criteria can be entered to manage the smart playlist. Selection criteria examples include a genre like Christmas music, songs that have not been played recently, or songs the user has listened to the most in a time period.

Library sharing

Through a "Home Sharing" feature, users can share their iTunes library wirelessly. Computer firewalls must allow network traffic, and users must specifically enable sharing in the iTunes preferences menu. iOS applications also exist that can transfer content without Internet. Additionally, users can set up a network-attached storage system, and connect to that storage system through an app.

Sound processing

iTunes includes sound processing features, such as equalization, "sound enhancement" and crossfade. There is also a feature called Sound Check, which normalizes the playback volume of all songs in the library to the same level.

Online music functionality

iTunes Store

Introduced on April 28, 2003, The iTunes Music Store allows users to buy and download songs, with 200,000 tracks available at launch. In its first week, customers bought more than one million songs. Music purchased was protected by FairPlay, an encryption layer referred to as digital rights management (DRM). The use of DRM, which limited devices capable of playing purchased files, sparked efforts to remove the protection mechanism. Eventually, after an open letter to the music industry by CEO Steve Jobs in February 2007, Apple introduced a selection of DRM-free music in the iTunes Store in April 2007, followed by its entire music catalog without DRM in January 2009.

iTunes in the Cloud and iTunes Match

In June 2011, Apple announced "iTunes in the Cloud", in which music purchases are stored on Apple's servers and made available for automatic downloading on other devices signed into the same account and, subject to continued availability, redownloading. Previously, purchases of music, video content, and iPod games (but not iOS apps) entitled the buyer to a single successful download. For music the user owns, such as content ripped from CDs, the company introduced "iTunes Match", a feature that can upload content to Apple's servers, match it to its catalog, change the quality to 256 kbit/s AAC format, and make it available to other devices.

Internet radio, iTunes Radio and Apple Music

When iTunes was first released, it came with support for the Kerbango Internet radio tuner service. In June 2013, the company announced iTunes Radio, a free music streaming service. In June 2015, Apple announced Apple Music, a subscription-based music streaming service, and subsequently integrated iTunes Radio functionality. Music tracks provided by Apple Music via iTunes are available at up to 256 kbit/s AAC fidelity. The Apple Music app also integrates Apple Music 1, a live music radio station.

Relocation of iTunes Features

As of 2024, Apple is phasing out iTunes in favour of three dedicated apps, Music, Podcasts, and TV, but the iTunes Store will still remain.

Other features

Video

In May 2005, video support was introduced to iTunes with the release of iTunes 4.8, though it was limited to bonus features part of album purchases. The following October, Apple introduced iTunes 6, enabling support for purchasing and viewing video content purchased from the iTunes Store. At launch, the store offered popular shows from the ABC network, including Desperate Housewives and Lost, along with Disney Channel series That's So Raven and The Suite Life of Zack & Cody. CEO Steve Jobs told the press that "We're doing for video what we've done for music — we're making it easy and affordable to purchase and download, play on your computer, and take with you on your iPod."

In 2008, Apple and select film studios introduced "iTunes Digital Copy", a feature on select DVDs and Blu-ray discs allowing a digital copy in iTunes and associated media players.

Podcasts

In June 2005, Apple updated iTunes with support for podcasts. Users can subscribe to podcasts, change update frequency, define how many episodes to download and how many to delete.

Similar to songs, "Smart playlists" can be used to control podcasts in a playlist, setting criteria such as date and number of times listened to.

Apple is credited for being the major catalyst behind the early growth of podcasting.

Apps

On July 10, 2008, Apple introduced native mobile apps for its iOS operating system. On iOS, a dedicated App Store application served as the storefront for browsing, downloading, updating, and otherwise managing applications, whereas iTunes on computers had a dedicated section for apps rather than a separate app. In September 2017, Apple updated iTunes to version 12.7, removing the App Store section in the process. iTunes 12.6.3 was released the following month, retaining App Store functionality, with 9to5Mac noting that the secondary release was positioned by Apple as "necessary for some businesses performing internal app deployments".. As of macOS 10.15 Catalina, the iTunes app has been replaced with the Music app, while still holding some iTunes functionality (such as browsing the store and buying items)

iTunes U

In May 2007, Apple announced the launch of "iTunes U" via the iTunes Store, which delivers university lectures from top U.S. colleges. With iTunes version 12.7 in August 2017, iTunes U collections became a part of the Podcasts app. On June 10, 2020, Apple formally announced that iTunes U would be discontinued at the end of 2021.

Apple mobile device connectivity

iTunes is required to activate early iPhone, iPod Touch, and iPad devices, although beginning with the iPhone 3G in June 2008 the devices could be activated at the point of sale by partecipating retailers. Since iOS 5, iOS devices can alternatively be activated and set-up on their own without requiring the use of iTunes.

iTunes also allows users to backup and restore the content of their Apple mobile devices, such as messages, photos, videos, application data and device settings and update or restore the firmware of their devices. However, as of iTunes 12.7, apps can no longer be purchased and installed using iTunes.

Ping

With the release of iTunes 10 in September 2010, Apple announced iTunes Ping, which CEO Steve Jobs described as "social music discovery". It had features reminiscent of Facebook, including profiles and the ability to follow other users. Ping was discontinued in September 2012.

Criticism

Security

The Telegraph reported in November 2011 that Apple had been aware of a security vulnerability since 2008 that would let unauthorized third parties install "updates" to users' iTunes software. Apple fixed the issue before the Telegraph's report and told the media that "The security and privacy of our users is extremely important", though this was questioned by security researcher Brian Krebs, who told the publication that "A prominent security researcher warned Apple about this dangerous vulnerability in mid-2008, yet the company waited more than 1,200 days to fix the flaw."

Software bloat

iTunes has been repeatedly accused of being bloated as part of Apple's efforts to turn it from a music player to an all-encompassing multimedia platform. Former PC World editor Ed Bott accused the company of hypocrisy in its advertising attacks on Windows for similar practices.