How to view, switch between, and close running applications
INSTRUCTIONS & INFO
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. Note: Multitasking is available on devices running iOS4 and later with apps that have been developed to work with iOS versions 4 and later.
Double tap the Home button to display recent apps.
Swipe left or right and locate the app you want to use.
Tap the app to switch to it. Note: Swipe up to reset or close an app.