Apple had declared during its iPhone OS 4 announcement that the iPhone 3GS, iPad, and iPod Touch will support a particular form of multitasking. The seven forms of supported multitasking are:
Background Audio: Audio services like Pandora and Slacker will transfer their streams to Apple’s background service and execute while you are on some other application.
Voice over IP: You can receive and make calls through Skype in the background. It is allowed for Talk1, Talk2 or any other VoIP Program.
Location Services: Background location services will permit GPS navigation apps continue to navigate while you might be on a phone call.
Push Notifications: Now developers can request to alert usersÂ through a cloud server when new information is available, such as current Facebook messages or news alerts.
Local Notifications: A third party app can set an alarm that pops up on the screen and tells you to bring it to the front.
Task Completion: The Task Completion function allows programs to complete various actions in the background, like uploading photos, videos, etc.
Fast App Switching: With fast app switching, apps can save their states so they can pop up to the foreground very quickly, as if they had been running all the time.
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