JellyLock7 cydia tweak is a lock screen app launcher, that is super convenient to use.
Drag a grabber to your favorite application to launch it without unlocking your device first.
Assign up to 5 shortcuts, that optionally display badges counting missed notifications. It features an option, allowing you to access your favorite apps without the need to enter your pass code. You can also change the circle size, color and alpha in Settings.