My apps.

Facebook.
Skype.
Tune in radio is awesome.
Starmap pro. Handy for star finding when out with the telescope.
Convert units. Handy for work.
Sky news
Sky +
Argos
Doodle god. Good fun game.
eBay
Flick fishing
Golf shot. Keeps your golf score for the course your playing.
Yelp. Handy for finding places to eat and such.
Phone jacker
Inbetweeners
Nike+gps. Keeps a track of your walks or runs.
My o2
Red laser. Scan a barcode and find out the price of the item.
Shazam
Itranslate
Get running
Nav free
Sleep talk
Solitaire


Loads more but not worth mentioning.