Very interesting article from Fraser Speirs, the developer of the Exposure iPhone application for interacting with Flickr.
I agree that we are just at the beginning of what Spiers identifies as the Type 3 or laptop replacement type applications. Sufficiently feature complete to let you do what you need to do without recourse to a full fledged computer, yet optimized for the touch interface rather than just being a simple port of an existing desktop application.
I think that he’s really correctly identified one of the key things for most iPhone users - you may be away from your computer, but you’re never away from your iPhone. I’ll leave my work supplied Blackberry on the desk while I go grab a coffee, or pop into another office without compunction. But go anywhere without the iPhone and I feel a pang of loss.
Just for fun, try going a couple of days without your iPhone. Pop the SIM card into a basic phone so that you’re still available, and see just how annoying it can be. On the other hand, I have begun reflecting each day on whether or not I really need to bring the laptop home every night. I still end up dragging it along most of the time, but this is a new choice that wasn’t really viable for me until the iPhone.