PagePreview allows you to preview springboard pages on your jailbroken iOS device by just dragging your finger on page indicator dots. You can also launch any application from the preview.

It is compatible with all jailbroken iOS devices including devices running iOS 4. PagePreview is developed by the same developer who made SBRotator (an application that allows the springboard to rotate in landscape mode with accelerometer). PagePreview is available at Cydia store for $1.74.