Not sure what kinda apps you're looking for but this is what I have on my Android:
WordFeud = good....basically scrabble
MyFitnessPal = syncs up with your online account
Shazam = I've not remembered to use it yet lol
Goodreads = like mpf syncs with online account
Viber = free calls and texts to anyone else that has it
Whatsapp = same as viber
Amazon = Don't think I've used it yet
Unblock Me = ADDICTIVE!!!!!
Juice Defender = Great for managing battery use
Photobucket = Uplads any photos or vids taken with my phone straight to photobucket
QR Droid = scans qr codes
Dominos = order pizza from your phone without talking to anone
Flashlight = soooo handy!!!
Kaspersky Mobile = Internet security I got free for delaying an order for my laptop internet security
IMDb = Sooo handy for a movie geek like me haha
YouTube = does what it says on the tin!
Sky News = as above
Sky Sports = great for checking scores when out and about!
TripAdvisor = handy for checking things out
WomanLog = tracking all things womanly
WikiEncyclopedia = great for looking things up
Angry Birds = but of course
Solitaire = I'm addicted!!
I also have an accuweather.com widget...why look outside when you have a phone!!
I have a few other apps but they are region specific so if you aren't in Ireland they would be no good for you!