Closing all background apps

[Beachball8]

How do I close all background apps simultaneously rather than 1 at a time?

 

[dtbratt]

How do I close all background apps simultaneously rather than 1 at a time?

Not possible unless you Jailbreak your iDevice.

 

[Julien]

How do I close all background apps simultaneously rather than 1 at a time?

Remove is the correct term since they are not open to close. Only certain Apps can keep predefined API's open in the background and icons show up in the menu bar to show this.