The app store is nice, well if you want 250 different fart button apps. Overall I have the impression that app quality has been on the decline.
This kills me. And I know Apple leeps strict control over the approval process, but I cannot stand the amount of useless garbage in there because the iPhone is the next big thing. I've got a few applications that I love:
1) Credit Card Application (I can charge clients using my Authorize.net merchant account right on my iPhone, they can even sign it, great!)
2) iBank Application (this is like Quicken for Mac, and they have an iPhone app that syncs, letting me know what's going on with my money at a glance)
3) Billings (time management and invoicing, great for freelances who may be doing work, but not necessarily at the computer, this syncs back to my desktop, too)
4) 1Password (I manage 400 something passwords, all unique, this makes sure I've got them all on my person in case I'm using a computer that isn't mine)
And then there's the neat games that cost $1 or $2, I think I've spent maybe $20 on games since I got the original iPhone shortly after launch. And the weather. And some other neat utilities.
Next I want to develop an application that people can use to record shutter speed, aperture, date/time and GPS coords when shooting film. I'd like for it to sync back to the computer and write itself to the EXIF of scanned images.