What are your favorite iPhone apps/games?

I've recently defected from Android (HTC Thunderbolt, rooted and running Cyanogenmod) to an iPhone 4S. I'm not as into the iPhone scene as I used to be (that shall soon change), but now that I've picked up the iPhone I need some apps to fill up my home screen! 

Some of my personal favorites so far are Instapaper (I cannot recommend it enough), Reeder, Canabalt, Jetpack Joyride, Instagram, Dropbox, Flashlight, Simplenote and the Chipotle app (I really like burritos). 

What are the apps you show off to others?