The first app. is Shutdown that switches off iPhone. It is useful if your sleep button is broken.
Other app is Lock, which locks your iPhone. It does the same as pressing sleep button on the top of the iPhone. Yet again if your sleep button doesn’t work this app is especially useful.
Shutdown and Lock is available from iClarified sources (http://installer.iclarified.com) found in iClarified category.
The las one is iReboot. Allows you to Reboot, Shutdown and Restart your iPhone. Shutdown will turn your iPhone completely off. Restart will respring your iPhone back to the lock screen.
iReboot is found from iSpazio (repo.ispazio.net) sources.