Hi all, I have upgraded into iPhone OS 4 yesterday and started to use some of the new features without problems such as folders, zooming in camera, new mail functionalities, etc. However, when I try to use multitasking it seems not working. I double-click on the home button but no apps appear, just transfers me into my favorites. Also, I can set up a background for my iphone, its only on the lock screen. Any help?