My top 5 iPhone apps:
5. Flashlight (surprising how much use this gets)
4. Gas Buddy (Obvious reasons)
3. Ebay (easier to use that the desktop site, especially combined with the camera for easy posting)
2. TrackThis (nothing like up-to-date packing tracking covering all carriers to keep track of all my incoming fragrances
1. Astrid (my life would be a mess without it's reminders)
Pandora was going to be on the list, but it's almost unusable due to how frequent the ads are.