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
Released to
June 21, 2010; 5 years ago (2010-06-21)
Latest release
iPhone 3G, iPod Touch (2nd generation)

4.2.1 (November 22, 2010; 5 years ago (2010-11-22)) [±]

iPhone 4 (CDMA)

4.2.10 (July 25, 2011; 4 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; 4 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
Support status
Unsupported as of about 2012[citation needed]

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 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.

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. iOS 4.3.5 was the final release on iOS 4.


iOS 4 added features such as multitasking, folders, and home screen wallpapers. Multitasking and home screen wallpapers were not available on the iPhone 3G and the iPod touch (2nd generation).

iOS 4.1 added a new app called Game Center, though not available on the iPhone 3G.


iPhone 3G users reported performance and battery issues. 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. 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: portable iOS devices[edit]

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.[1]

Supported devices[edit]


  1. ^ "About Apple TV (2nd generation) software updates". December 14, 2010. Retrieved January 9, 2011. 
Preceded by
iPhone OS 3
iOS 4
June 2010
Succeeded by
iOS 5