iOS 4

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iOS 4

iOS 4 is a mobile operating system created by Apple Inc and was released on 2010 June 24th. It is the 4th major release of iOS, and the first release to be named iOS, the previous releases were known as iPhoneOS It succeeded iPhoneOS 3 and it was succeeded by iOS 5 on 2011 October 12th.

Feature changes

iOS 4 introduced folders on the home screen, significantly increasing the number of apps that can be displayed.

Support for custom wallpapers was also added, although limited to newer devices due to animation performance requirements.

The operating system also added a multitasking feature, letting apps dealing with Internet calling, location and audio playback function in the background, whereas a similar but more restricted "Fast App Switching" technology enabled any app to be left inactive in the background while users switch to other apps.

iOS 4 also added a system-wide spell checking feature, enabled iBooks on iPhone, unified the Mail inbox to combine content from different email providers, and introduced both Game Center for social gaming and FaceTime for video calling.

The iOS 4 update introduced performance and battery problems on iPhone 3G devices, with Apple investigating the matter and promising then-upcoming updates.

However, the company became the subject of a lawsuit from an unsatisfied customer over the issues. Around the same time, the release of iPhone 4 and its subsequent antenna problems made Apple focus on unsuccessfully attempting to patch the issues with software updates.

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Version history

4.0 June 21, 2010 Initial release; Initial release for iPhone 4 GSM

4.0.1 July 15, 2010 Carrier signal strength calculation method changed, after Antennagate, Exchange account bug fixed.

4.0.2 August 11, 2010 Security fix for an exploit taking advantage of PDF file format vulnerabilities.

4.1 September 8, 2010 Initial release on iPod Touch (4th generation); new features:

HDR support for photos captured with the iPhone 4

Game Center;

Ability to upload high definition videos captured on the iPhone 4 to YouTube and MobileMe;

Bug fixes and performance improvements.

4.2.1 November 22, 2010 Initial release for iPad; last version to run on iPhone 3G and iPod touch (2nd generation) due to hardware and performance issues.

4.2.5 January 11, 2011 Initial release on iPhone 4 (CDMA model). Exclusive to this device; Wi-Fi hotspot support

4.2.6 January 31, 2011 Bug fixes for Wi-Fi hotspot

4.3 March 4, 2011 Initial release on iPad 2; unavailable on iPhone 4 (CDMA); new features include support for personal Wi-Fi hotspots, iTunes home sharing, improvements to AirPlay, and other minor improvements

4.3.1 March 25, 2011 Fix for iPod Touch screen glitches; stability improvements for cellular connectivity on iPhone models

4.3.2

4.2.7 April 14, 2011 Fixes for frozen calls on FaceTime and connectivity issues on cellular models of iPad

4.3.3

4.2.8 May 4, 2011 Fixes for location service

4.3.4

4.2.9 July 15, 2011 Security fixes

4.3.5

4.2.10 July 25, 2011 Security update to fix certificate validation

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Specifications

Developer Apple Inc.

Source model Closed, with open source components

Initial release 2010 June 24th

Latest release 4.3.5

Platforms

iPhone

iPhone 3G

iPhone 3GS

iPhone 4S

iPod Touch

iPod Touch (2nd generation)

iPod Touch (3rd generation)

iPod Touch (4th generation)

iPad

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

Support status

Partially historic, partial third party app support. Drops support for the iPhone (1st generation), and iPod Touch (1st generation).

This section was modified from Wikipedia

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Sources

Wikipedia

Other sources are needed, and this article needs LOTS of improvement and original work to prevent it from being half a copy and paste from Wikipedia.

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Article info

Written on: 2021 Monday September 20th at 3:48 pm

Last revised on: 2021 Monday September 20th at 3:48 pm

File format Markdown document (*.md *.mkd *.markdown)

Article version: 1 (2021 Monday September 20th at 3:48 pm)

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