Activator lets you open or "activate" apps on your jailbroken iPhone via special gestures, buttons and shortcuts, instead of requiring you to return to the homescreen and tapping on an icon every time.
Multifl0w is a multitasking interface for Backgrounder which displays applications that are running and allows you to scroll left and right between them for quick switching. It also includes a snapshot of each of the backgrounded applications.
A front-end addon for Backgrounder, Circuitous provides a clean interface for switching between apps and multitasking on your jailbroken iPhone. It shows your open applications in a nice dock on the right side of the screen from which you can launch and exit apps.
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