Calendar-Fantastical
Weather-Today Weather
Camera-Kitcam
Calculator-Calculator by Bricko Apps
Reminders-Omnifocus
Clock-Yocto Alarm
Compass-CFSAC it has a flashlight too
Contacts/Phone-Cobook
Notes-Evernote or Scratch
Maps-Google Maps
Im sure there is more i use but thats all i can think of now