iOS 4

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iOS 4
A release of the iOS operating system
IOS4 logo.png
IOS 4.jpg
iOS 4.3 running on an iPhone 4.
Developer Apple Inc.
Source model Closed, with open source components
Released to
manufacturing
June 21, 2010; 4 years ago (2010-06-21)
Latest release 4.3.4 (all models)
4.3.5 (iPad 2 only) / July 25, 2011; 3 years ago (2011-07-25)
Platforms iPhone 3G, iPhone 3GS, iPhone 4, iPod touch (2nd generation), iPod touch (3rd generation), iPod touch (4th generation), iPad (1st generation), iPad 2
Kernel type Hybrid (XNU)
License Proprietary EULA except for open-source components
Preceded by iPhone OS 3.x
Succeeded by iOS 5
Official website www.apple.com/ios/

iOS 4 is the fourth version of the iOS mobile operating system designed by Apple Inc.. It was released on June 21, 2010, and was the first release to be renamed to simply "iOS". It was the first major iOS release to drop support for some devices and the first major iOS release that iPod Touch users did not have to pay for.

The iPhone 3G and 2nd generation iPod Touch lack multitasking capabilities and the ability to set a home screen wallpaper, while the iPhone 4, iPhone 3GS, 3rd and 4th generation iPod Touch have them. The iPhone and the 1st generation iPod Touch cannot run iOS 4 and above.

iOS 4.2.1, released November 22, 2010, added iPad compatibility. It was the last to support iPhone 3G and iPod Touch (2nd generation, MB & MC models).

iOS 4.0 was released to the public and supported only the iPhone and iPod touch. iOS 4.0 was announced to have over 1500 new APIs for developers, supporting the highly anticipated multitasking feature. The final iOS version for the 2nd generation iPod Touch and iPhone 3G is iOS 4.2.1. iOS 4.2.1 was the first version to bring major feature parity to the iPhone and iPad. The release of the CDMA iPhone 4 for Verizon Wireless saw a branching of iOS. The 4.2 version sequence continued for the CDMA iPhone 4 while iOS 4.3 was released for all other products.

Version history: portable iOS devices[edit]

Main article: History of iOS
Table of versions: iOS 4.x – iPhone, iPad, iPod touch
Version Build Baseband Release date Features
iPhone 3G, iPhone 3GS, iPhone 4 and iPod Touch (2nd and 3rd generation)

4.0[edit]

8A293 P2 P3 P4 T2 T3 05.13.04 P2 P3

01.59.00 P4

June 21, 2010

iPhone and iPod Touch only

  • User interface for app switching by double clicking Home button.
  • Portrait orientation lock.P3,P4,T3
  • iPod control widget.
  • FaceTime direct video calling ability over Wi-Fi (iPhone 4 and later, iPod Touch (4th generation), iPad 2, and Mac OS X users).
  • iBooks sync support through iTunes for iPhone and iPod Touch.
  • iAd mobile advertising network.
  • Settings
  • App-specific location settings.
  • Cellular data toggle (on-off).
  • "Complex Password" setting: passwords with alphabet characters and numbers.
  • Simple Passcode Lock (4 digit number) option.
  • New wallpapers.
  • Wallpaper available for Home screen.P3,P4,T3
  • New wallpaper preview for Home screen and lock screen.
  • Set up Internet tethering.
  • New Gmail and Exchange icons in Mail, Contacts, Calendars account settings.
  • Support multiple Exchange accounts.
  • Custom Dictionary.
  • Airplane Mode for iPod Touch.
  • Separated Sounds settings from General settings.
  • Home screen
  • Ability to categorise apps into folders with default folder naming based on category name in App Store.
  • Up to 2,160 instead of 180 visible apps (12 apps per folder).
  • Folder name supports up to 13 characters.
  • Custom Home screen wallpaper.
  • Dock redesigned to that of the iPad.
  • Rate on deleting app removed.
  • Default Utilities folder which contains the Clock, Calculator, Voice Memos and Compass apps.
  • Revised SpringBoard scrolling.
  • Camera
  • Up to 5x digital (as opposed to optical) zoom feature on the Camera app.
  • Photos
  • Categorised by Albums, Faces, Events and Places (under iPhoto in Mac OS X).
  • Select multiple photos for mass deletion.
  • Support landscape mode.
  • Camera Roll
  • Categorisation by All, Photos and Videos.
  • Support landscape mode.
  • App Store
  • Ability to gift apps.
  • Maps
  • Unified "locate me" icon.
  • Background location icon shown on status bar.
  • iPod
  • Playlist creation on device.
  • Nested playlists.
  • Lyrics and Podcast info on Setting.
  • Volume control with Bluetooth headsets.
  • Album art displayed in Album view.
  • Notes
  • Notes syncing with MobileMe, Gmail IMAP and Yahoo! Mail.
  • Accounts management appears if syncing is enabled.
  • Notes setting below Mail, Contacts, Calendars Settings if syncing is enabled.
  • Moved search box into title bar.
  • Calendar
  • Birthday calendar.
  • CalDAV invitations.
  • Ability to edit which calendar an event is located in after the initial saving.
  • Ability to select any combination of calendar categories to view.
  • Contacts
  • Unified info by linking contacts from different accounts.
  • CardDAV.
  • Streamlined "New Contact" screen.
  • Spotlight
  • Search with Web or Wikipedia.
  • Search Messages.
  • Safari (Webkit version 532.9)
  • Bing is now a search option, along with Google and Yahoo!.
  • Recent searches below search field.
  • Top hit in search.
  • Suggestions appear below search field for all 3 search engines.
  • Unified "Search" keyboard button when search field being used.
  • In-page audio playback.
  • Voice control
  • The ability to ask what the current time is.P3,P4,T3
  • YouTube
  • Rotate & zoom videos in vertical and horizontal position.
  • Latest 480p for smoother and quicker video playback.
  • Accessibility
  • Larger fonts in Mail, SMS & alerts.P3,P4,T3
  • Automatically speak auto-corrections and auto-capitalisations.
  • Message
  • Include a Search bar.
  • Character count (can be enabled or disabled in Settings > Messages screen).
  • Failed SMS notification.
  • Option to toggle off the ability to send group messages.
  • Mail
  • Unified inboxes.
  • Edit from outbox.
  • Support for multiple Exchange accounts.
  • File & delete Mail search results.
  • Organise by thread in Mail.
  • Quick look attachments.
  • Open attachments by registered filetype with corresponding apps from the App Store.
  • Smart links for dates and addresses.
  • Contact pictures in emails.
  • Create Calendar events from dates within emails.
  • International
  • Spell check.
  • Added Cangjie and Wubihua keyboards for Simplified and Traditional Chinese.
  • Text replacement between Simplified and Traditional Chinese.
  • Switch keyboard shortcut (holding the "Earth" button on keyboard for a while).
  • Added support for Danish voice control.
  • New languages added (Catalan, Hungarian, Vietnamese).
  • Other
  • Support for Apple Bluetooth keyboards.P3,P4,T3
  • Persistent Wi-Fi.
  • Added support for iBooks application.
  • Wake on wireless.
  • Auto-join and auto-login and IPv6 on individual Wi-Fi networks setting.
  • Enhanced data protection.P3,P4,T3
  • Wireless app distribution.
  • Mobile device management.
  • SSL VPN support (both Juniper and Cisco).
  • Microsoft Exchange Server 2010 support.
  • Improved Bluetooth driver for A2DP devices.
  • Improved iOS animations.

4.0.1[edit]

8A306 P2 P3 P4 05.13.04 P2 P3

01.59.00 P4

July 15, 2010

iPhone only

  • Updated carrier signal strength display.
  • Increase in the length of the smaller signal bars.
  • The method in which signal strength is calculated was modified (as a result of the antennagate issue).
  • Fixed Exchange ActiveSync issues.
  • Only official SIM card number can be used for FaceTime identification.

4.0.2[edit]

8A400 P2 P3 P4 T2 T3 05.13.04 P2 P3

01.59.00 P4

August 11, 2010

iPhone and iPod Touch only

iPhone 3G, iPhone 3GS, iPhone 4 and iPod Touch (2nd, 3rd and 4th generation)

4.1[edit]

8B117 P2 P3 P4 T2 T3 T4 05.14.02 P2 P3

02.10.04 P4

September 8, 2010

iPhone and iPod Touch only

  • Improved calendar colours.
  • Bug fixes
iPhone 3G, iPhone 3GS, iPhone 4, iPod Touch (2nd, 3rd and 4th generation), and iPad (1st generation)

4.2.1[edit]

8C148 P2 P4 T2 T3 T4 S1 S1C

8C148a P3

05.15.04 P2 P3

03.10.01 P4
07.10.00 S1C

November 22, 2010[9]

For iPhone, iPad, and iPod touch

  • Bug fixes
  • Birthdays calendar does not display birthdays starting more than 77 years ago.[10]
  • AirPlay (replacement of AirTunes, AirPlay will offer stream video, music, and photos over Wi-Fi).[11]
  • AirPrint wireless printing with Print Center (select models).[11]
  • Import .ics calendar files directly for events.
  • Improved battery performance.
  • Birthdays icon has been changed in the Calendar app.
  • Updated Carrier Settings (US is AT&T 9.0, UK is O2 9.1, Germany is Deutsche Telekom 9.0).
  • Text search on web pages.P3 P4 T3 T4[11]
  • 2 new fonts for Notes in Settings (Helvetica and Chalkboard).
  • Safari 6533.18.5, WebKit 533.17.9.
  • Added support for Chinese URL over Safari.[12]
  • Added an indicator in the App Store which shows if an app supports Game Center.
  • Support for CoreMIDI.
  • YouTube voting.[13]
  • Minor improvements in UI graphics.
  • New parental controls for deleting apps, changing mail accounts and location services.[13]
  • The font size of text in Calendar can now be changed in the Accessibility settings.[14]
  • Security fixes.[15]
  • Network-controlled fast dormancy implemented in baseband to improve battery life and reduce network congestion.[16]
  • Fixes intermittent Wi-Fi issues in iOS 4.2 beta 3, which were retained in iOS 4.2 GM.
  • Fixes VoIP issues.
  • Fixes Car Stereo "music skip" issues.[citation needed]
  • Find My iPhone location feature is free (iPhone 4, iPod Touch (4th generation), & iPad) running on iOS 4.2.1.P4, T4, S1, S1C

iPad only

  • 4.x support for the iPad.[11]
  • iOS 4 features for iPad (multitasking, folders, etc.).
  • Up to 4,400 icons instead of 220 (20 apps a folder).
  • Updated carrier signal strength display (3G iPad only).
  • Increase in the length of the smaller signal bars.
  • The method in which signal strength is calculated has been enhanced.
  • Additions to the multitasking tray.
  • Brightness.
  • Volume control.
  • AirPlay controls.
  • Screen rotation lock switch.
  • Physical iPad screen rotation lock switch is converted into a sound/silent switch in iOS 4.2 (just like on the iPhones), with a virtual screen rotation lock switch added to the multitasking tray.
  • More than 30 new keyboards and dictionaries, including Arabic, Greek, and Hebrew.
  • New multitasking animation.
  • New bookmarks design.

iPhone and iPod Touch only

  • Bug fixes.
  • Fixes glitch that can let a user get into the Phone app while the phone is locked via "Emergency Call" by dialing a random number and quickly pressing the lock button after dialing that call.[17]
  • Fixes the alarm bug caused by daylight saving time changing, affected on a part of iPhone and iPod Touch owners living in various countries.[18]
  • Improved iPhone 3G and iPod Touch (2nd generation) performance.[19]
  • Additions to multitasking tray.
  • Volume controls.
  • AirPlay controls.
  • New Voice Memos icon.
  • Ability to initiate FaceTime calls from Voice Control.
  • FaceTime shortcut from Messages app (iPhone 4 only).[13]
  • New text tone alerts (New & Original tone lists) (iPhone 4 only).
  • Ringer & alerts on/off switch (Settings > Sounds) for volume buttons (iPhone only).
  • Assign different text tone alerts to each contact.
  • Restores full field test mode.
iPhone 4 (CDMA (Verizon) version) only

4.2.2[edit]

8E128 P4C 1.0.05 P4C February 7, 2011 CDMA (Verizon) iPhone 4 only
  • Initial release on iPhone 4 (CDMA, Verizon version).
  • Personal Hotspot feature.

4.2.3[edit]

8E200 P4C 1.0.05 P4C February 10, 2011 CDMA (Verizon) iPhone 4 only

Bug fixes

  • Personal Hotspot bug fixes.

4.2.4[edit]

8E303 P4C 1.0.06 P4C April 14, 2011 CDMA (Verizon) iPhone 4 only
  • Security update.
  • Baseband update.

4.2.5[edit]

8E401 P4C 1.0.06 P4C May 4, 2011 CDMA (Verizon) iPhone 4 only

Bug fixes

  • Reduced size of the iOS crowd-sourced location database cache.
  • No longer backs the cache up to iTunes.
  • Deletes it entirely when Location Services is turned off.

4.2.6[edit]

8E501 P4C 1.0.06 P4C July 15, 2011 CDMA (Verizon) iPhone 4 only

Security Updates

  • Disabled the possibility of viewing a maliciously crafted PDF file that may lead to an unexpected application termination or arbitrary code execution.
  • Disabled a malicious code running as the user may gain system privileges.

4.2.7[edit]

8E600 P4C 1.0.06 P4C July 25, 2011 CDMA (Verizon) iPhone 4 only

Security Update

  • Fixes a security vulnerability with certificate validation.
iPhone 3GS, iPhone 4 (GSM version only), iPod Touch (3rd and 4th generation), iPad (1st generation) and iPad 2

4.3[edit]

8F190

8F191 S2 S2C S2D

05.16.01 P3


04.10.01 P4 S2C

07.11.00 S1C

2.0.4 S2D

March 9, 2011
  • Initial release on iPad 2.
  • Implementation of ASLR for increased security.
  • AirPlay video support for third party apps.
  • HTTP Live Streaming statistics.
  • New font in Notes app ("Noteworthy").
  • Improved Safari performance with "Nitro" JavaScript engine.
  • Redesigned “account” section under the Store menu.
  • Ability to switch on automatic downloads (for iTunes Music and App Store applications).
  • Location services have been shifted from General to Settings menu.
  • New parental controls for use with Ping.
  • New menu for scrubbing in videos.
  • Fine scrubbing: adjust by seconds / frames.
  • Quarter scrubbing: second.
  • Half speed scrubbing: adjust by minute(s).
  • Hi-speed scrubbing: run fast through minutes.
  • Ability to cancel and delete an app which is currently downloading. Before iOS 4.3, it was only possible to delete an app which had already downloaded.
  • Stream from an iTunes library to iOS using Home Sharing.
  • In-app purchases always ask for a password, even if one has previously been entered.
  • Internal system clock gets network time updated more frequently via NITZ (part of the official GSM standard since phase 2+ release 96) and gives a more accurate time for the device, it updates about every five days.

iPhone only

  • Personal Hotspot feature (Wi-Fi hotspot with up to 5 simultaneous devices (Wi-Fi hotspot iPhone 4 only[20])) on supported carriers.
  • Ability to set amount of times a text tone repeats (up to 10 times).
  • In field test mode refresh button has been removed & updated information has been displayed in bottom of the screen (it updates every 4–6 seconds).
  • Slideshow options moved to Photos app.
  • New look for taking a picture for a Contact.
  • When receiving a text message, the iPhone now vibrates 2 times.
  • Some SMS tones have been shortened.

iPod Touch only

iPad only

  • Ability to choose function of iPads physical switch between rotation lock or mute.
  • Fullscreen iAd banner format.
  • Photo Booth & FaceTime app (iPad 2 only).

Bug fixes

  • Fixed issue that prevented controls from being dismissed in some cases.
  • Addressed issue where the keyboard could not be brought back when highlighting and swiping through search results.
  • VoiceOver now reads the entire chart in Stocks app while in landscape mode.
  • Fixed slideshow stop after 15 images when using AirPlay.
  • 05.16.01 (for iPhone 3GS), 04.10.01 (for iPhone 4).
  • Updated carrier settings (US is AT&T 10.0, UK is O2, 10.0, Portugal is Optimus 10.0).
  • Enabled traffic volume indicator IE.[clarification needed] in cell update (iPhone and iPad Wi-Fi + 3G only).
  • Fixed canceled recurring calendar events still showing on the event list.
  • Fixed deleting a recurring event make the alarm go away.
  • Fixed all-day alarm fired an hour early.
  • Fixed missing accented letters in European keyboard popups.
  • Increase font size for China and Pinyin inputs.
  • Fixed auto-correction issue when switch back from Emoji to English keyboard.
  • Fixed orientation of mail application not following device orientation under specific conditions.
  • Fixed mail message view and orientation when quickly selecting a message and hitting edit mode.
  • Fixed MMS messages with vCards scrolling up.
  • Added [Address Space Layout Randomisation] (ASLR).[21]
  • Added new icon for Wi-Fi tethering for personal hotspot on status bar.
  • Fixed issue that caused Safari and other apps to crash after loading certain heavy Web sites.
  • Fixed Personal Hotspot password failure with 22+ characters.
  • Added support for “find” in Safari.
  • Fixed wallpaper titles for VoiceOver.

4.3.1[edit]

8G4 05.16.02 P3


04.10.01 P4 S2C

07.11.01 S1C

2.0.4 S2D

March 25, 2011

Bug fixes

  • Fixed graphics glitches on iPod Touch (4th generation).
  • Baseband updates for the iPhone 3GS and iPad (1st generation).
  • Fixed memory hang that results in memory corruption when reading large files from USIM filesystem.
  • Fixed problem with NTLM authentication in apps and on websites.
  • Fixed issue with the Springboard and 3rd party apps not recognizing the gyroscope on the iPad 2.
  • Resolves bugs related to activating and connecting to some cellular networks.
  • Fixes image flicker when using Apple Digital AV Adapter with some TVs.
  • Resolves an issue authenticating with some enterprise web services.
  • Changes the behaviour of the battery percentage.

4.3.2[edit]

8H7P3 P4 S1 S2 S2C T3 T4


8H8S2D

05.16.02 P3


04.10.01 P4 S2C

07.11.01 S1C

2.0.4 S2D

April 14, 2011

Bug fixes

  • Fixed issue with blank or frozen video during (or before) a FaceTime call.
  • Fixed issue with connectivity to 3G networks on iPad Wi-Fi + 3G.
  • Fixed issue where Exchange redirection does not occur when Activesync server is on an Exchange 2010 server and user mailbox is on Exchange 2007.

4.3.3[edit]

8J2P3 P4 S2 S2C S2D T3 T4


8J3S1 S1C

05.16.02 P3


04.10.01 P4 S2C

07.11.01 S1C

2.0.4 S2D

May 4, 2011

Bug fixes

This update contains changes to the iOS crowd-sourced location database cache.

  • Reduced size of the iOS crowd-sourced location database cache.
  • No longer backs the cache up to iTunes.
  • Deletes it entirely when Location Services is turned off.
  • No longer allows user to remove apps that have not been completely downloaded.

4.3.4[edit]

8K2 05.16.02 P3


04.10.01 P4 S2C

07.11.01 S1C

2.0.4 S2D

July 15, 2011
  • Re-introduced the ability to cancel and delete apps that are currently downloading.
  • Jailbreaking patches.
  • Disabled the possibility of viewing a maliciously crafted PDF file that may lead to an unexpected application termination or arbitrary code execution.
  • Disabled a malicious code running as the user may gain system privileges.
  • Disabled "incomplete signing attacks", blocking "Untethered" jailbreak.

4.3.5[edit]

8L1 04.10.01 S2C

2.0.4 S2D

July 25, 2011; 3 years ago (2011-07-25)

iPad 2 only

Security Update

  • Fixes a security vulnerability with certificate validation.
Version Build Baseband Release date Features


Version history: Apple TV (2nd generation) onwards[edit]

Main article: iOS version history

iOS 4.1 was the first version of iOS available on the Apple TV (2nd generation). It included Apple TV Software 4.0.[22]

Table of versions: iOS 4.x – Apple TV (2nd generation) onwards
iOS version Apple TV Software Build Release date Features

4.1[edit]

4.0 8M89
September 1, 2010
  • Initial release on Apple TV (2nd generation)

4.2[edit]

4.1 8C150 (1539) November 22, 2010

4.2.1[edit]

4.1.1 8C154 (1553) December 14, 2010

Bug fixes

  • Addresses an issue that causes some high-definition TVs to incorrectly display at 480p.
  • Addresses an issue that may cause a movie or TV show to be re-downloaded.[22]

4.3[edit]

8F191m (2060) March 9, 2011
  • AirPlay video support for third party apps on iDevices.
  • New slideshow themes: View photos with the new Scrapbook, Photo Mobile, and Holiday Mobile slideshow themes.
  • Improved on-screen keyboard: Search and enter names and passwords more easily with the redesigned on-screen keyboard.
  • Enjoy Dolby Digital 5.1 surround sound when watching Netflix.
4.2.1 8F202 (2100) March 22, 2011

Bug fixes

  • Addresses issues that may cause the screen to flicker or display incorrect colour on some older TVs.
  • Addresses an issue where Apple TV may not wake up from sleep.
  • Addresses an issue where audio may not be heard on some TV models after switching from another input.
  • Apple TV Software 4.2.1 includes stability and performance fixes for Apple TV.[22]
4.2.2 8F305 (2203) May 11, 2011

Bug fixes

  • Addresses an issue in which audio is not output when playing some video content.
  • Addresses an issue in which video is not displayed when playing some content.
  • Adds an audio output setting for switching to 16-bit audio for compatibility with some TVs and AV receivers.
  • Improves the performance of fast-forwarding and rewinding live events.
  • Addresses an issue in which the description information is not displayed for some movies.
  • Addresses an issue in which YouTube subscription videos are not ordered by date.
4.3 8F455 (2557) August 1, 2011
  • Ability to watch videos from Vimeo.
  • US-only feature: streams purchased TV shows from iTunes on Apple TV (and past purchases). Previously, only rentals were available.
iOS Version Apple TV Software Build Release date Features

Problems[edit]

On the iPhone 3G, there can be some battery life problems.[citation needed]

Lag on the iPhone 3G[edit]

iPhone 3G users that have an iPhone 3G with iOS 4 have complained about their iPhone 3G running slow.[citation needed]

Notes[edit]

See also[edit]

References[edit]

  1. ^ "About the security content of the iOS 4.0.2 Update for iPhone and iPod Touch". Apple Inc. 2010-08-11. Retrieved 2010-09-02. 
  2. ^ a b "Apple announces iOS 4.1". Engadget. September 8, 2010. 
  3. ^ a b c d "New Features in the iOS 4.1 Software Update". Apple Inc. September 2010. 
  4. ^ "Game Center compatible with 2nd-gen iPod Touch, not iPhone 3G". AppleInsider. September 2010. 
  5. ^ "About the security content of iOS 4.1 for iPhone and iPod Touch". Apple Inc. September 2010. 
  6. ^ "iOS 4.1 Beta 3 enables e-mail based FaceTime calls". iLounge. August 2010. 
  7. ^ "iPhone and iPod Touch: Syncing Notes". Apple. September 2010. 
  8. ^ "iOS 4.1 Restores Field Test Mode". Mac Rumors. September 2010. 
  9. ^ "Apple’s iOS 4.2 Available Today for iPad, iPhone & iPod Touch". Apple. 22 Nov 2010. 
  10. ^ Apple Knowledge Base
  11. ^ a b c d "iOS 4.2 Software Update coming in November". Apple Inc. September 2010. 
  12. ^ "Chinese URL supporting over Safari in iOS 4.2". Smallcampus.net (alex18181818). 9 November 2010. 
  13. ^ a b c "iOS 4.2 packs new, improved YouTube, FaceTime features and more". AppleInsider. September 2010. 
  14. ^ "Apple – iOS 4.2 Software Update". 
  15. ^ "About the security content of iOS 4.2". Apple. November 23, 2010. 
  16. ^ "iOS 4.2 supports new tech to reduce network congestion, Nokia Siemens says". Engadget. November 30, 2010. 
  17. ^ Taimur Asad, "Apple Acknowledges iOS 4.1 Security Flaw. Will Fix it in November with iOS 4.2", Redmond Pie, October 27, 2010
  18. ^ "Apple planning to fix the Australian daylight saving alarm bug by releasing the new version of iOS". AppAdvice. October 12, 2010. 
  19. ^ "iOS 4.2 bringing speed improvements to iPhone 3G?". Engadget. 2010-11-08. Retrieved 2011-01-09. 
  20. ^ "iPhone: System needs for Personal Hotspot". Retrieved 17 May 2011. 
  21. ^ Bright, Peter (2011-03-11). "Pwn2Own day 2: iPhone, BlackBerry beaten; Chrome, Firefox no-shows". Ars Technica. Retrieved 2013-03-21. 
  22. ^ a b c "About Apple TV (2nd generation) software updates". Support.apple.com. December 14, 2010. Retrieved January 9, 2011.