5 Good apps for the new iPhone 4S owner

Like many of you I am the owner of a brand new iPhone 4S (white, 32GB). I have shared my thoughts on the phone after just a day of ownership, and am getting overwhelmed with queries about which apps I am using. Apps and iPhones go together like music and iTunes so it's a fair question.
See also: iPhone 4S: Day 1 with an Android phone owner
Like everyone else, with only a few days to play with the iPhone, I haven't had time to try a bunch of apps. I have settled on five of them that I use more than the others. These are third party apps available in the App Store; no Apple apps are in this list. There are about a million apps in the store so this list is a bit incomplete and I will be fleshing it out over time.. If you have a favorite app on your iPhone give it a shout out in the comments below as we're all looking for gems.
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