The Android system doesn't need you to close a running app for every instance. But in some cases you may need to force stop an app that's misbehaving, or like playing a game, you may need to actually close the app in order to start a new level rather than continuing the last. Here are the steps to follow:
Run the Settings app and tap Apps under DEVICE.
Select the app you want to close.
Tap the 'Force stop' button and tap 'OK' to confirm.
Run the Settings app and tap Apps under DEVICE.
Select the app you want to close.
Tap the 'Force stop' button and tap 'OK' to confirm.
