* refer to http://xaviesteve.com/disable-multitasking-in-ios4-no-jailbreaking-needed/

Simply change the property of multitasking as false in /System/Library/CoreServices/SpringBoard.app/NxxAP.plist. The reference web page shows N82AP.plist, but currently it’s N88AP.plist. I didn’t look further, but I could guess its name would be changed in time.

Using ssh/scp, you can copy it from/to Mac and manipulate it.