|A version of the iOS operating system|
iOS 4 running on an iPhone 4.
|Source model||Closed, with open source components|
|June 21, 2010|
|Latest release||4.3.4 (all models)
4.3.5 (iPad 2 only) / July 25, 2011
|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|
|Unsupported as of 2013 for iOS 4.2.1 or earlier, Limited third-party application support for iOS 4.3 and above.|
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
Version history: Apple TV (2nd generation) onwards
iOS 4.1 was the first version of iOS available on the Apple TV (2nd generation). It included Apple TV Software 4.0.
On the iPhone 3G, there can be some battery life problems.
Lag on the iPhone 3G
iPhone 3G users that have an iPhone 3G with iOS 4 have complained about their iPhone 3G running slow.
- "About Apple TV (2nd generation) software updates". Support.apple.com. December 14, 2010. Retrieved January 9, 2011.