Most of the apps I use the most I learned about from net discussion. I thought it might be fun to share some of the add ons, there is a lot out there....I'm not including the ones that came with the phone.

Gas Buddy - find cheap gas
Flashlight - I am surprised at how handy this has been
MW Dictionary. I love looking up definitions on the fly.
Yelp restaurant reviews on the fly
Star Walk astonomy app, OMG this is so cool and you do not have to be connected to a data network or wifi for it to work. I used it in the Grand Canyon!!
Grocery IQ.Keeps all my lists in one place.