Switching Between Open Apps
It’s not immediately obvious when apps are running in the background of your iPhone. That is, there’s no “switch apps” or “view running apps” button; instead, you have to know the correct tap sequence to view and switch to apps that are paused in the background.
What you have to do is double-tap the Home button (that’s the big physical button at the bottom of your iPhone). This displays all paused and recently used apps, four at a time, at the bottom of the screen. To view additional apps, swipe the screen to the left.
Figure 1 Double-tap the Home button to view paused apps at the bottom of the screen.
To switch to one of these paused apps, tap it. The currently running app will be paused (and added to the paused list), while the app you just tapped will move front and center, ready to resume wherever it last left off.
Closing Open Apps
Note that because the iPhone doesn’t employ true multi-tasking, the apps you see when you double-tap the Home button are not necessarily open or in use. Thus most of these apps do not take up valuable system memory and resources.
That said, if you notice your iPhone starting to run slower or your battery starting to drain faster, it’s likely that one or more of these paused apps are actually running in the background, consuming system resources. To save battery life, you can manually close any or all paused apps.
To do this, double-tap the Home button to display all paused and recently used apps. Press and hold one of these apps and they all start to wiggle, with a little minus sign (-) on the top left corner. Tap the red minus sign to close that app – and free up system resources. Tap the Home button to stop the apps from wiggling and return to normal operation.
Figure 2 Tap the red minus sign to close an open app.