Since the release of iOS 2.0, users were annoyed that Apple (s aapl) hadn’t yet implemented multitasking — the ability to run more than one application at a time — on the iPhone. Fast forward two years to the release of iOS 4.0, when Apple finally introduced the feature. Some users may not yet have a good grasp on how to use iOS multitasking, yet, though. For those users, here’s multitasking explained.
When you’re running an application that supports multitasking (all of Apple’s apps do, as well as many from the App Store), all you have to do is exit the application like you normally would, using the Home button. The application is automatically suspended and is waiting in the background for you to open it back up again. Not all apps are actually suspended though; there are some applications which will continue running even when they’re closed, such as music players and navigation apps. There’s no need to treat these applications differently, though. If the developers of the app have included support for running in the background, it will happen automatically.
The same thing happens when you receive a call on your iPhone; the application is suspended and sent to the background, ready for when you finish talking.
Returning to an App
When you’re ready to go back to an app waiting in the background, simple press the Home button twice quickly. This opens the multitasking bar, which shows you all the applications which are currently open on your device.
Simply tap an app’s icon to open it back up. It will open as usual, but will resume from exactly how it was when you closed it (if it supports auto-resume). For instance, if you were using a to-do list application, and you were halfway through editing an item, the app will open at the editing screen again and you’ll be able to carry on from where you were. This also happens if you come back from a call. The app you had open when the call came in will return in the same place it was.
Close Running Applications
In some rare cases, you may want to stop an application which is waiting in the background. To do this, open up the multitasking bar with a double-tap of the Home button. Then, find the app you want to close, and press and hold its icon. The apps in the bar will wiggle, like when you organize the Home screen, and red minus icons will show up above each app. Just tap a minus icon, and the corresponding application will be closed. It won’t be in the background, so the next time you open it, it will start from the first screen again, not from where you were when you last had it open.
More Multitasking Bar Features
The multitasking bar also houses some other useful features. If you swipe your finger to the right, a set of controls appears which allow you to control any music playing on your device, as well as lock the orientation of the screen. The iPad also features two sliders, one for the volume and one for the screen brightness. The iPod controls work with your device’s iPod music as you’d expect, but they also work for a music application running in the background. For example, start listening to the Pandora app and the controls will work with Pandora.
To stop your screen rotating when you turn the device (useful for reading in bed), tap the grey icon on the left. That’s the orientation lock switch, which determines whether the screen will rotate or not.
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