Those are the hidden system applications of iOS.
Setup - the welcome to iPhone screen you get when you set up a new iPhone
FieldTest - accessible through the phone app, it displays information about the cell towers
iOS Diagnostics - Used by Apple store employees to gather information about your iPhone, usually at the genius bar
AdSheet - I am unaware, most likely to do with iAds.
They are normal apps on all iPhones, they are just usually hidden. Cydia installs applications into the same place system apps are stored, so I believe they just happen to show up.
Just respring and they should go away.
Thanks,
Brian