3.21428571428571 24 5 0

It is the fourth generation of Apple's iPhone Operating System that powers their popular iPhone, iPod Touch, and iPad devices.

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smart multitasking lets you have multiple applications running while preserving battery life

15 agree

folders are useful

11 agree

allows users to set their own wallpapers

10 agree

new enterprise features including remote management, wireless app distribution

9 agree

new mail app: includes multiple exchange accounts, centrallized inbox, threaded messages, and fast inbox switching

8 agree

Background location updating will let some cool apps be made such as tracking a bike trip

8 agree

Game Center could do for mobile games what Xbox Live did for console games

8 agree

Good amount of options for managing your location settings

6 agree

iAd is a brand new form of advertising - could revolutionize ads the same way AdSense did

6 agree

still available for older iPhone 3G / iPod Touch 2nd gen - albeit without multitasking (due to slower hardware)

6 agree

will be available on iPad

4 agree

no flash, floppy, or other outdated technology

4 agree

improved spotlight functionality allows for direct searching of Wikipedia, Google

4 agree
  • Only 3 words are allowed.

Still no Adobe Flash

7 agree

Multitasking won't be supported on the iPhone 3G/iPod Touch 2nd Gen and older platforms

6 agree

not true multitasking - but app switching, applications are 'paused' besides a few key tricks like background VOIP, audio playback, location data

6 agree

will inevitably diminish battery life (due to improved multitasking functionality)

5 agree

iAds could make apps become overwhelmed with ads - similar to Made For AdSense sites

5 agree

won't be available for the iPad until the fall - where multitasking is needed most

5 agree

concurrent apps can be closed by the iPhone OS whenever it thinks it's "necessary" - user doesn't have full control

3 agree

even more restrictive NDA license agreement: limits devs to 3 languages, bans cross-platform dev tools, bans use of 3rd party APIs and frameworks

3 agree

no multi/centrallized notification area

3 agree

no audio profiles for different volume/ring settings for different environments

3 agree

No custom sms ringtones

2 agree

upgrade can take a LONG time

2 agree

no background images for iPhone 3G

2 agree

Background location is scary from a privacy perspective

2 agree

Having to listen to a lot of 'analysts' about what iPad 'may', 'could', 'won't' and 'will inevitably' do

1 agrees
  • Only 3 words are allowed.


iPhone OS 4 is the fourth generation of Apple's iPhone Operating System that powers their popular iPhone, iPod Touch, and iPad devices. With this iteration Apple responds to many of their critics in incorporating application multitasking and background processing. However, in true Apple fashion, they have devised their own take on these features that they claim preserves battery life and responsiveness while offering the ability to run and switch between multiple applications. This differs from a typical multi-tasking implementation as Apple created seven new services that the OS can run in the background and that 3rd party apps have access to, but the actual 3rd party apps are paused and resumed rather than concurrently executed. Alongside multitasking Apple introduces some other major functionality in iPhone OS 4, including a comprehensive gaming social network akin to Xbox Live, and a rich integrated ad platform called iAd. It must be noted that some functions such as multitasking are not compatible with iPhone versions older than the 3GS.

Additions with this Release
  • limited background processing
    • background audio - for apps like Pandora and stream music while using other applications
    • Voice over IP - for apps like Skype receive calls even when it's not open
    • Background location - for apps like Loopt to automatically update your location
    • Push notifications
    • Local notifications
    • Task completion - for apps like flickr to continue uploading a photo even after the app is closed
    • Fast app switching
  • change your homescreen wallpaper
  • homescreen folders
    • drag and drop apps on top of one another to automatically create app group folders
  • enhanced mail app
    • unifies inboxes
    • view e-mails as conversations
  • enhanced enterprise features
  • cross game mobile social network (a la Xbox Live)
    • matchmaking
    • achievements
  • iAd
    • in-app advertising platform that's run on the OS level. Let's you interact with ads without leaving an app
  • more API functions for developers
Multitasking Details

To preserve battery life background applications are run in a limited state that can perform a limited set of functions that Apple claims are the most crucial. Switching between applications is accomplished through a mini-dock that comes up when you press the home button twice.

While programs are running in the background they have access to a limited set of core functionality. Specifically they can play music, start or continue Voice over IP calls, update location information, display notifications, and complete started tasks. Apple claims that these services will provide the key functionality that people want from the apps while not compromising battery life or performance.


The iAd platform is part of the core operating system. This means that apps can have rich, interactive advertisements that don't require you to leave the app. Apple claims that this will let people engage with the ads better, which will let developers monetize off their free applications better. The hope for end users is that there will be even more, and better quality free apps.

Post Review
12/01/2010 10:31

Weird. Statcounter reports that Blackberry OS trumps Apple iOS for mobile web browsing for the first time. That seems backwards:

tags: #rim_blackberry_os_6 #ios_4

07/07/2010 08:01

There's a performance benchmark with Android 2.2 (Froyo)'s new browser: Ars Technica: Android 2.2 demolishes iOS4 in JavaScript benchmarks.

Note that these benchmarks are only JavaScript, and you'll see the major advantage over iOS as shown in the benchmarks only on JavaScript-heavy sites. On "normal" sites the browsers are head-to-head in loading speed, however, Froyo integrates a full Adobe Flash 10.1, which Apple's iOS doesn't.

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