To see which apps you have open, swipe up the home key .
To switch to another app, swipe right.
To close an app, swipe it up.
To go back to the previous screen you were in, tap the back key . Your phone remembers all the apps and websites you've visited since the last time your screen was locked.
To go to the home screen, tap the home key . The app you were in stays open in the background.