iOS 4

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iOS 4
A version of the iOS operating system
IOS4 logo.png
IOS 4 Homescreen.png
iOS 4 running on an iPhone 4.
Developer Apple Inc.
Source model Closed, with open source components
Initial release June 21, 2010; 6 years ago (2010-06-21)
Latest release
iPhone 3G, iPod Touch (2nd generation)

4.2.1 (November 22, 2010; 6 years ago (2010-11-22)) [±]

iPhone 4 (CDMA)

4.2.10 (July 25, 2011; 5 years ago (2011-07-25)) [±]

iPhone 3GS, iPhone 4 (GSM), iPod Touch (3rd generation), iPod Touch (4th generation), iPad (1st generation), iPad 2
4.3.5 (July 25, 2011; 5 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
Succeeded by iOS 5
Official website iOS 4 at the Wayback Machine (archived June 30, 2010)
Support status
Unsupported as of about 2013[citation needed]

iOS 4 is the fourth major release of the iOS mobile operating system designed by Apple Inc.. It was released on June 21, 2010, and was the first major release to be renamed to simply "iOS", and the first major release to drop support for some devices, as well as the first update that iPod Touch users did not have to pay for.[1][2] iOS 4 was succeeded by iOS 5, which was released on October 12, 2011.


iOS 4 was introduced during the annual Apple Worldwide Developers Conference on June 7, 2010 together with the iPhone 4. With the release of the first-generation iPad earlier that year, the company renamed iPhone OS to iOS to reflect the entire family of devices.[2] iOS 4.0 supported only the iPhone and iPod touch at launch, but later added iPad support.[1] It also added over 1500 new APIs for developers, including the highly anticipated multitasking feature.

iOS 4.2.1, released November 22, 2010, was the first version to bring major feature parity to the iPhone and iPad.[3][4] It was also the last to support the iPhone 3G and iPod Touch (2nd generation, MB & MC models).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. iOS 4.3.5 was the final release on iOS 4.



iOS 4 raised the maximum number of home screen apps from 180 to 2160 due to the addition of folders. These folders would automatically be named based on the containing apps' respective App Store category. The ability to add custom wallpapers to the homescreen was also added (not supported on iPhone 3G and 2nd generation iPod Touch).[5]The dock was also redesigned to be more reflective and match that of Mac OS X 10.5-10.6.


iOS 4 introduced Multitasking. It allows user to switch between the apps instantly by double clicking the home button. It was implemented in such a way that did not cause excessive battery drain or a large performance hit.[1][6] The iPhone 3G and 2nd generation iPod Touch lack multitasking capabilities because of hardware limitations.


Main article: FaceTime

iOS 4 supports FaceTime, the video-chatting feature that debuted on the iPhone 4. It allows the user to perform face-to-face video conversation by just clicking the FaceTime button during a phone call or directly from the FaceTime app.[2] It required a WiFi connection to work at the time.

Game Center[edit]

Main article: Game Center

iOS 4.1 added a new app called Game Center, an online multiplayer social gaming network,[6] which allows users to invite friends to play the game and to compare their scores on a leaderboard. It was not available on the iPhone 3G.

Other new features[edit]


iOS 4 added support for Apple Bluetooth Keyboards on iPhone 3GS, iPhone 4 and 3rd Generation iPod Touch.


Safari on iOS 4 added Bing as a search option in addition to Google and Yahoo!. A unified "Search" keyboard button was added when the search field was being used.[7]


iPhone 3G users reported performance and battery issues after they updated to the latest software.[8][9] As a result, Apple released iOS 4.1 and 4.2.1 in attempt to fix the performance issues.

Some iPhone 4 users have reported technical problems with the antennas.[10] Some carriers sued for smartphone’s defective antenna design which drops calls and has a weak signal.[11] Apple eventually released iOS 4.2.1 and the CDMA Verizon iPhone 4 running iOS 4.2.2 in attempt to fix the problem.

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

iOS 4.1 was the first version of iOS available on the Apple TV (2nd generation). It included Apple TV Software 4.0.[12]

Supported devices[edit]

The 1st generation iPhone and the 1st generation iPod Touch cannot run iOS 4 and above due to hardware limitations.[1]


  1. ^ a b c d "iOS 4: What you need to know". Macworld. Retrieved October 29, 2016. 
  2. ^ a b c Chartier, David (Jun 7, 2010). "iPhone OS gets new name, video calling". MacWorld. Retrieved 2016-08-20. 
  3. ^ "Apple releases iOS 4.2.1". Macworld. Retrieved October 29, 2016. 
  4. ^ "Apple - Press Info - Apple's iOS 4.2 Available Today for iPad, iPhone & iPod touch". Retrieved 2016-10-29. 
  5. ^ "Hands on with iOS 4 folders". Macworld. Retrieved 2016-10-29. 
  6. ^ a b "What's New in iOS 4". Apple. Retrieved June 14, 2010. 
  7. ^ "Bing & Yahoo Prompting iPhone Users To Switch Search Engines". Search Engine Land. 2010-06-24. Retrieved 2016-10-29. 
  8. ^ Ogg, Erica (July 28, 2010). "Apple to investigate iOS 4 problems on iPhone 3G". CNET. 
  9. ^ Ogg, Erica (November 4, 2010). "Apple sued for iOS 4 problems on iPhone 3G, 3GS". CNET. 
  10. ^ Chen, Brian X. "Tests Confirm iPhone 4's Antenna Flaws (Updated)". WIRED. Retrieved 2016-10-29. 
  11. ^ Staff, Computerworld. "Apple, AT&T Sued Over iPhone 4 Antenna Problems". WIRED. Retrieved 2016-10-29. 
  12. ^ "About Apple TV (2nd generation) software updates". December 14, 2010. Retrieved January 9, 2011. 

External links[edit]

Preceded by
iPhone OS 3
iOS 4
June 2010
Succeeded by
iOS 5