Wednesday, 1 August 2012

Multitasking in Apple iphone

iOS: Understanding multitasking


Summary

Multitasking is a feature of iOS that allows applications to perform specific tasks in the background while you are using another application. This article explains which features use multitasking, how to switch between apps, and how to troubleshoot multitasking.

Products Affected

iPad, iPhone, iPod touch
Multitasking in iOS allows you to switch instantly between apps and to resume an app. When you return to an app, you can pick up right where you left off. Multitasking doesn't slow down the performance of the foreground app or drain battery life unnecessarily.
Follow these steps to switch quickly between apps:
  1. Double-click the Home button to display recently used apps.
    Multitasking bar
  2. Swipe left or right and locate the app you want use.
  3. Tap the app to switch to it.

Understanding Multitasking and recently used apps

Double-clicking the Home button displays a list of recently used apps. These apps are not necessarily actively in use, open, or taking up system resources. They will instantly launch when you return to them. Certain tasks or services can continue to run in the background. You can distinguish most of these by checking the status bar:
  • Location Services / GPS: When in use, the icon appears in the status bar. If an app is using location services, you can pause this service within the app.
    Note: You can view a list of apps that recently used location services in Settings > Location Services.
  • Audio playback: When listening to music or other audio sources, the icon appears in the status bar. If an app is using playback, you can pause or stop playback from within the app. You don't need to close or quit the application.
  • iTunes syncing: When the icon appears in the status bar, the device is tethered or wirelessly syncing with iTunes.
  • Network activity: When the icon appears in the status bar, network activity is occuring. The network-activity indicator will appear only for the following features or activities, when you're using the corresponding app:
    • Photo Stream uploads and downloads
    • Regular application downloads from the App Store
    • Automatic downloads (music, books, and applications)
    • iTunes Match downloads
    • Checking email
    • iCloud restores
Some third-party apps may also use the icon to show an active process.
  • Voice over IP (VoIP): A double-height status bar will appear when you leave the primary VoIP app, such as Skype.
For additional tips on how to optimize your settings for maximum battery life for your iOS device, see the Apple battery page.

Additional Information

Note: Multitasking is supported on iPhone 3GS or later, iPod touch (3rd generation or later), and all iPad models using iOS 4 or later.
If an app unexpectedly quits, doesn't respond to your input, or doesn't perform as expected, do the following, testing after each step:
  1. Check for app updates.
  2. Restart your device.
  3. Force the specific app to close
  4. Update your iOS device.
If you continue to experience issues with an app from the App Store, see this article.
Important: Information about products not manufactured by Apple is provided for information purposes only and does not constitute Apple’s recommendation or endorsement. Please contact the vendor for additional information.
Reference: Apple website <<<<<<<<click to get detail
Video available in http://www.youtube.com/watch?gl=US&v=7_Wz1nxOz6Q