The iPod is a line of portable media players designed and marketed by Apple Inc. The first line was released on October 23, 2001, about 8½ months after iTunes (Macintosh version) was released. Its most recent redesigns were announced on September 12, 2012. There are four current versions of the iPod: the ultra-compact iPod Shuffle, the compact iPod Nano, the touchscreen iPod Touch, and the hard drive-based iPod Classic.
Like other digital music players, iPods can serve as external data storage devices. Storage capacity varies by model, ranging from 2 GB for the iPod Shuffle to 160 GB for the iPod Classic. The devices are controlled by the Samsung ARM and the Apple A5 CPUs.
Apple's iTunes software (and other software) can be used to transfer music, photos, videos, games, contact information, e-mail settings, Web bookmarks, and calendars, to the devices supporting these features from computers using certain versions of Apple Macintosh and Microsoft Windows operating systems.[1][2]
Prior to iOS 5, the iPod branding was used for the media player included with the iPhone and iPad, a combination of the Music and Videos apps on the iPod Touch. As of iOS 5, separate apps named "Music" and "Videos" are standardized across all iOS-powered products.[3] While the iPhone and iPad have essentially the same media player capabilities as the iPod line, they are generally treated as separate products. During the middle of 2010, iPhone sales overtook those of the iPod.[4]
Contents
[show]History
See also: Timeline of Apple Inc. products
Though the iPod was released in 2001, its price and Mac-only compatibility caused sales to be relatively slow until 2004.[5] The iPod line came from Apple's "digital hub" category, when the company began creating software for the growing market of personal digital devices. Digital cameras, camcorders and organizers had well-established mainstream markets, but the company found existing digital music players "big and clunky or small and useless" with user interfaces that were "unbelievably awful,"[6] so Apple decided to develop its own. As ordered by CEO Steve Jobs, Apple's hardware engineering chief Jon Rubinstein assembled a team of engineers to design the iPod line, including hardware engineers Tony Fadell and Michael Dhuey,[7] and design engineer Sir Jonathan Ive.[6] Rubinstein had already discovered the Toshiba disk drive when meeting with an Apple supplier in Japan, and purchased the rights to it for Apple, and had also already worked out how the screen, battery, and other key elements would work.[8] The product ("the Walkman of the twenty-first century" [9]) was developed in less than one year and unveiled on October 23, 2001. Jobs announced it as a Mac-compatible product with a 5 GB hard drive that put "1,000 songs in your pocket."[10]
Apple did not develop the iPod software entirely in-house, instead using PortalPlayer's reference platform based on two ARM cores. The platform had rudimentary software running on a commercial microkernel embedded operating system. PortalPlayer had previously been working on an IBM-branded MP3 player with Bluetooth headphones.[6] Apple contracted another company, Pixo, to help design and implement the user interface under the direct supervision of Steve Jobs.[6] As development progressed, Apple continued to refine the software's look and feel. Starting with the iPod Mini, the Chicago font was replaced with Espy Sans. Later iPods switched fonts again to Podium Sans—a font similar to Apple's corporate font, Myriad. iPods with color displays then adopted some Mac OS X themes like Aqua progress bars, and brushed metal meant to evoke a combination lock. In 2007, Apple modified the iPod interface again with the introduction of the sixth-generation iPod Classic and third-generation iPod Nano by changing the font to Helvetica and, in most cases, splitting the screen in half by displaying the menus on the left and album artwork, photos, or videos on the right (whichever was appropriate for the selected item).
In 2006 Apple presented a special edition for iPod 5G of Irish rock band U2. Like its predecessor, this iPod has engraved the signatures of the four members of the band on its back, but this one was the first time the company changed the colour of the metal (not silver but black). This iPod was only available with 30GB of storage capacity. The special edition entitled purchasers to an exclusive video with 33 minutes of interviews and performance by U2, downloadable from the iTunes Store.[11][12]
In September 2007, during a lawsuit with patent holding company Burst.com, Apple drew attention to a patent for a similar device that was developed in 1979. Kane Kramer applied for a UK patent for his design of a "plastic music box" in 1981, which he called the IXI.[13] He was unable to secure funding to renew the US$ 120,000 worldwide patent, so it lapsed and Kramer never profited from his idea.[13]
The name iPod was proposed by Vinnie Chieco, a freelance copywriter, who (with others) was called by Apple to figure out how to introduce the new player to the public. After Chieco saw a prototype, he thought of the movie 2001: A Space Odyssey and the phrase "Open the pod bay door, Hal!", which refers to the white EVA Pods of the Discovery One spaceship. Chieco saw an analogy to the relationship between the spaceship and the smaller independent pods in the relationship between a personal computer and the music player.[6] Apple researched the trademark and found that it was already in use. Joseph N. Grasso of New Jersey had originally listed an "iPod" trademark with the U.S. Patent and Trademark Office (USPTO) in July 2000 for Internet kiosks. The first iPod kiosks had been demonstrated to the public in New Jersey in March 1998, and commercial use began in January 2000, but had apparently been discontinued by 2001. The trademark was registered by the USPTO in November 2003, and Grasso assigned it to Apple Computer, Inc. in 2005.[14]
The earliest recorded use in commerce of an "iPod" trademark was in 1991 by Chrysalis Corp. of Sturgis, Michigan, styled "iPOD".[15]
Hardware
| Chipset or Electronic | Product(s) | Component(s) |
|---|---|---|
| Microcontroller | iPod Classic first to third generations | Two ARM 7TDMI-derived CPUs running at 90 MHz |
| iPod fourth and fifth generations, iPod Mini, iPod Nano first generation | Variable-speed ARM 7TDMI CPUs, running at a peak of 80 MHz to save battery life | |
| iPod Nano second generation | Samsung System-on-a-chip, based around an ARM processor.[16][17] | |
| iPod Shuffle first generation | SigmaTel STMP3550 chip that handles both the music decoding and the audio circuitry.[18] | |
| iPod Touch first and second generation | ARM 1176JZ(F)-S at 412 MHz for first gen, 533 MHz for second gen. | |
| iPod Touch third and fourth generation | ARM Cortex A8 at 600 MHz for third gen, 800 MHz for fourth gen. | |
| Audio Chip | All iPods (except the iPod Shuffle, 6G Classic and 2G Touch)[19] | Audio Codecs developed by Wolfson Microelectronics |
| Sixth-generation iPod Classic | Cirrus Logic Audio Codec Chip | |
| Storage Medium | iPod Classic | 45.7 mm (1.8 in) hard drives (ATA-6, 4200 rpm with proprietary connectors) made by Toshiba |
| iPod Mini | 25.4 mm (1 in) Microdrive by Hitachi and Seagate | |
| iPod Nano | Flash Memory from Samsung, Toshiba, and others | |
| iPod Shuffle and Touch | Flash Memory | |
| Batteries | iPod first and second generation, Shuffle | Internal Lithium Polymer Batteries |
| iPod third generation onward, iPod Mini, iPod Nano, iPod Touch, fourth generation iPod Shuffle (including maybe earlier) | Internal Lithium-Ion Batteries | |
| Display | iPod Nano | 2.5-inch (diagonal) Multi-Touch, 432-by-240 resolution at 202 pixels per inch[20] |
| iPod Classic | 2.5-inch (diagonal) color LCD with LED backlight, 320-by-240 resolution at 163 pixels per inch[21] | |
| iPod Touch | 4-inch (diagonal) widescreen Multi-Touch, 1136-by-640 resolution at 326 pixels per inch[22] |
Audio
The third-generation iPod had a weak bass response, as shown in audio tests.[23][24] The combination of the undersized DC-blocking capacitors and the typical low-impedance of most consumer headphones form a high-pass filter, which attenuates the low-frequency bass output. Similar capacitors were used in the fourth-generation iPods.[25] The problem is reduced when using high-impedance headphones and is completely masked when driving high-impedance (line level) loads, such as an external headphone amplifier. The first-generation iPod Shuffle uses a dual-transistor output stage,[23] rather than a single capacitor-coupled output, and does not exhibit reduced bass response for any load.
For all iPods released in 2006 and earlier, some equalizer (EQ) sound settings would distort the bass sound far too easily, even on undemanding songs.[26][27] This would happen for EQ settings like R&B, Rock, Acoustic, and Bass Booster, because the equalizer amplified the digital audio level beyond the software's limit, causing distortion (clipping) on bass instruments.
From the fifth-generation iPod on, Apple introduced a user-configurable volume limit in response to concerns about hearing loss.[28] Users report that in the sixth-generation iPod, the maximum volume output level is limited to 100 dB in EU markets. Apple previously had to remove iPods from shelves in France for exceeding this legal limit.[29]
Connectivity
See also: Dock connector#Apple
Originally, a FireWire connection to the host computer was used to update songs or recharge the battery. The battery could also be charged with a power adapter that was included with the first four generations.
The third generation began including a 30-pin dock connector, allowing for FireWire or USB connectivity. This provided better compatibility with non-Apple machines, as most of them did not have FireWire ports at the time. Eventually Apple began shipping iPods with USB cables instead of FireWire, although the latter was available separately. As of the first-generation iPod Nano and the fifth-generation iPod Classic, Apple discontinued using FireWire for data transfer (while still allowing for use of FireWire to charge the device) in an attempt to reduce cost and form factor. As of the second-generation iPod Touch and the fourth-generation iPod Nano, FireWire charging ability has been removed. The second-, third-, and fourth-generation iPod Shuffle uses a single 3.5 mm minijack phone connector which acts as both a headphone jack and a data port for the dock.
The dock connector also allowed the iPod to connect to accessories, which often supplement the iPod's music, video, and photo playback. Apple sells a few accessories, such as the now-discontinued iPod Hi-Fi, but most are manufactured by third parties such as Belkin and Griffin. Some peripherals use their own interface, while others use the iPod's own screen. Because the dock connector is a proprietary interface, the implementation of the interface requires paying royalties to Apple.[30]
Apple introduced a new 8-pin dock connector, named Lightning, on September 12, 2012 with their announcement of the iPhone 5, the fifth generation iPod Touch, and the seventh generationiPod Nano, which all feature it. The new connector replaces the older 30-pin dock connector used by older iPods, iPhones, and iPads. Apple Lightning cables have pins on both sides of the plug so it can be inserted with either side facing up.[31]
Accessories
Many accessories have been made for the iPod line. A large number are made by third party companies, although many, such as the iPod Hi-Fi, are made by Apple. Some accessories add extra features that other music players have, such as sound recorders, FM radio tuners, wired remote controls, and audio/visual cables for TV connections. Other accessories offer unique features like the Nike+iPodpedometer and the iPod Camera Connector. Other notable accessories include external speakers, wireless remote controls, protective case, screen films, and wireless earphones.[32] Among the first accessory manufacturers were Griffin Technology, Belkin, JBL, Bose, Monster Cable, and SendStation.
BMW released the first iPod automobile interface,[33] allowing drivers of newer BMW vehicles to control an iPod using either the built-in steering wheel controls or the radio head-unit buttons. Apple announced in 2005 that similar systems would be available for other vehicle brands, including Mercedes-Benz,[34] Volvo,[35]Nissan, Toyota,[36] Alfa Romeo, Ferrari,[37] Acura, Audi, Honda,[38] Renault, Infiniti[39] and Volkswagen.[40] Scion offers standard iPod connectivity on all their cars.
Some independent stereo manufacturers including JVC, Pioneer, Kenwood, Alpine, Sony, and Harman Kardon also have iPod-specific integration solutions. Alternative connection methods include adapter kits (that use the cassette deck or the CD changer port), audio input jacks, and FM transmitters such as the iTrip—although personal FM transmitters are illegal in some countries. Many car manufacturers have added audio input jacks as standard.[41]
Beginning in mid-2007, four major airlines, United, Continental, Delta, and Emirates, reached agreements to install iPod seat connections. The free service will allow passengers to power and charge an iPod, and view video and music libraries on individual seat-back displays.[42] Originally KLM and Air France were reported to be part of the deal with Apple, but they later released statements explaining that they were only contemplating the possibility of incorporating such systems.[43]
Software
The iPod line can play several audio file formats including MP3, AAC/M4A, Protected AAC, AIFF, WAV, Audible audiobook, and Apple Lossless. The iPod photo introduced the ability to display JPEG, BMP, GIF, TIFF, and PNG image file formats. Fifth and sixth generation iPod Classics, as well as third generation iPod Nanos, can additionally play MPEG-4 (H.264/MPEG-4 AVC) and QuickTime video formats, with restrictions on video dimensions, encoding techniques and data-rates.[44] Originally, iPod software only worked with Mac OS; iPod software for Microsoft Windows was launched with the second generation model.[45] Unlike most other media players, Apple does not support Microsoft's WMAaudio format—but a converter for WMA files without Digital Rights Management (DRM) is provided with the Windows version of iTunes. MIDI files also cannot be played, but can be converted to audio files using the "Advanced" menu in iTunes. Alternative open-source audio formats, such as Ogg Vorbis and FLAC, are not supported without installing custom firmware onto an iPod (e.g., Rockbox).
During installation, an iPod is associated with one host computer. Each time an iPod connects to its host computer, iTunes can synchronize entire music libraries or music playlists either automatically or manually. Song ratings can be set on an iPod and synchronized later to the iTunes library, and vice versa. A user can access, play, and add music on a second computer if an iPod is set to manual and not automatic sync, but anything added or edited will be reversed upon connecting and syncing with the main computer and its library. If a user wishes to automatically sync music with another computer, an iPod's library will be entirely wiped and replaced with the other computer's library.
Interface
iPods with color displays use anti-aliased graphics and text, with sliding animations. All iPods (except the 3rd-generation iPod Shuffle, the 6th & 7th generation iPod Nano, and iPod Touch) have five buttons and the later generations have the buttons integrated into the click wheel – an innovation that gives an uncluttered, minimalist interface. The buttons perform basic functions such as menu, play, pause, next track, and previous track. Other operations, such as scrolling through menu items and controlling the volume, are performed by using the click wheel in a rotational manner. The 3rd-generation iPod Shuffle does not have any controls on the actual player; instead it has a small control on the earphone cable, with volume-up and -down buttons and a single button for play and pause, next track, etc. The iPod Touch has no click-wheel; instead it uses a 3.5" touch screen along with a home button, sleep/wake button and (on the second and third generations of the iPod Touch) volume-up and -down buttons. The user interface for the iPod Touch is identical to that of the iPhone. Differences include a lack of a phone application. Both devices use iOS.
iTunes Store
Main articles: iTunes and iTunes Store
The iTunes Store (introduced April 29, 2003) is an online media store run by Apple and accessed through iTunes. The store became the market leader soon after its launch[46] and Apple announced the sale of videos through the store on October 12, 2005. Full-length movies became available on September 12, 2006.[47]
At the time the store was introduced, purchased audio files used the AAC format with added encryption, based on the FairPlay DRM system. Up to five authorized computers and an unlimited number of iPods could play the files. Burning the files with iTunes as an audio CD, then re-importing would create music files without the DRM. The DRM could also be removed using third-party software. However, in a deal with Apple, EMI began selling DRM-free, higher-quality songs on the iTunes Stores, in a category called "iTunes Plus." While individual songs were made available at a cost of US$1.29, 30¢ more than the cost of a regular DRM song, entire albums were available for the same price, US$9.99, as DRM encoded albums. On October 17, 2007, Apple lowered the cost of individual iTunes Plus songs to US$0.99 per song, the same as DRM encoded tracks. On January 6, 2009, Apple announced that DRM has been removed from 80% of the music catalog, and that it would be removed from all music by April 2009.
iPods cannot play music files from competing music stores that use rival-DRM technologies like Microsoft's protected WMA or RealNetworks' Helix DRM. Example stores include Napster and MSN Music. RealNetworks claims that Apple is creating problems for itself[48] by using FairPlay to lock users into using the iTunes Store. Steve Jobs stated that Apple makes little profit from song sales, although Apple uses the store to promote iPod sales.[49] However, iPods can also play music files from online stores that do not use DRM, such as eMusic or Amie Street.
Universal Music Group decided not to renew their contract with the iTunes Store on July 3, 2007. Universal will now supply iTunes in an 'at will' capacity.[50]
Apple debuted the iTunes Wi-Fi Music Store on September 5, 2007, in its Media Event entitled "The Beat Goes On...". This service allows users to access the Music Store from either an iPhone or an iPod Touch and download songs directly to the device that can be synced to the user's iTunes Library over a WiFi connection, or, in the case of an iPhone, the telephone network.
Games
Main articles: iPod game and App Store (iOS)
Video games are playable on various versions of iPods. The original iPod had the game Brick (originally invented by Apple's co-founder Steve Wozniak) included as an easter egg hidden feature; later firmware versions added it as a menu option. Later revisions of the iPod added three more games: Parachute, Solitaire, and Music Quiz.
In September 2006, the iTunes Store began to offer additional games for purchase with the launch of iTunes 7, compatible with the fifth generation iPod with iPod software 1.2 or later. Those games were: Bejeweled, Cubis 2, Mahjong,Mini Golf, Pac-Man, Tetris, Texas Hold 'Em, Vortex, Asphalt 4: Elite Racing and Zuma. Additional games have since been added. These games work on the 6th and 5th generation iPod Classic and the 5th and 4th generation iPod Nano.
With third parties like Namco, Square Enix, Electronic Arts, Sega, and Hudson Soft all making games for the iPod, Apple's MP3 player has taken steps towards entering the video game handheld console market. Even video game magazines like GamePro and EGM have reviewed and rated most of their games as of late.[51]
The games are in the form of .ipg files, which are actually .zip archives in disguise[citation needed]. When unzipped, they reveal executable files along with common audio and image files, leading to the possibility of third party games. Apple has not publicly released a software development kit (SDK) for iPod-specific development.[52] Apps produced with the iPhone SDK are compatible only with the iOS on the iPod Touch and iPhone, which cannot run clickwheel-based games.
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