Here are a list of my favorite all time apps- I have more, but these are the ones I’ve found to be either irreplaceable in terms of what they can do, or just flat out awesome.

Photographers Contract Maker- Allows photographers to make contracts on the go!
Flixster- Check local movie listing times.
Storyboard Maker- Allows directors to plan movie shots and sequences.
Netflix- Streaming movies to your computer or wireless device.
Flashlight- A way to use your iPhone as a weak light source, great for painting with light.
WhiteNoise-
Facebook-

Games-
Geocaching
Fieldrunners
Plants vs Zombies
Shredder Chess