The apps I used a lot are
Evernote - Such a great app and its free on the android. You can take text,pic, and video notes and sync it autmatically to your computer.
WhatsAPP - Again its free on the android, really cool app if you want to have a text convo with a group of your friends on androids and other devices like Blackberry & iPhones. I use this mainly to chat at the same time to my friends.
And other apps I use..mainly cos I read a lot of stuff online.
I have Mashable, Entrepreneur, StumbleUpon, TweetDeck, Soccer Live Scores, Dropbox, Greader, Liverpool RSS, Skype, JustPictures, HD Wallpapers, Job Search, and a few others lol
Thats pretty much it.
I have HTC Hero!