Multifl0w is a new Multitasking Interface for iPhone. Task switching on iPhone has become much easier with Multifl0w, which is one of the most desired features of the iPhone.
The app is free for trial basis and will be charged $5 thereafter. The app is available on Jailbreak app store Rock Your Phone and soon will be available on Cydia. Check out the screenshots of the app:
A video of the app:
P.S: The app is available only on jailbroken iPhone. You can jailbreak your iPhone with Blackra1n.