The only thing I haven't found is a way to kill all background apps. Not necessary but deeply satisfying.
I found this in another thread -
How to close apps in multitasking..
In the app bar on the bottom of the screen you press and hold the app icon until a little red circle with a minus sign appears at the top left corner of the icon. tap the little red minus circle and the app closes.
I think he was wanting to close all apps, not just one at a time.
I use an app for that, SwitcherPlus--alas, it is a jailbreak app but it is free. It greatly increases the capability of the task/app switcher.
When you press and hold an app in the switcher it will now have the usual "-" icon but also one on the bottom with an arrow pointing to the right. Tapping that arrow will close the app, but also all apps to the right of it too. Very handy. If you do it to the first app in the list, all apps are closed.
Better yet I have assigned apps to be excluded from that "mass closure." So they stay in the list unless I close them explicitly (using the "-" icon).
Finally I can have favorite apps that always appear in the switcher on the right... in the order I place them (not practical to have more than just a few). Very handy app... wish you didn't have to be jailbroken to get it.
Michael