Apple did it! Hosted mobile applications on the iPhone are powerful and useful. We've long desired a useful browser on a mobile device, but no-one has pulled it off; until now. I've been involved in many efforts to wedge a full-blown browser onto tiny solid-state devices; from AOL's Gamera project to Mozilla's minimo, but in each one of those situations tried to solve the problem by stripping down the browser to get it to fit into some horribly restrictive hardware and operating system environment. We constantly wrestled between that approach, and the "just get the hardware and operating system to look like a PC" approach; tens of millions of dollars were spent chasing the former; the wrong one.
Now I'm sure Safari has been cobbled a bit to get onto the iPhone, but for all intents and purposes it's the same as the desktop version (great CSS, JS, XML support; note, Safari is still hindered by lacking native stylesheet translation though; bizarre). This allows the end user to finally have a true web browsing experience on a small mobile device.
Apple's API for iPhone web development allows for native OS look and feel applications to be run on the iPhone via Safari. This is a great thing for end users and web app developers. It's also a joyous occasion now that the carriers have been circumvented. For years they've crippled mobile application development for selfish control reasons; finally there's an option that pulls it all together, all the while on a major US mobile carrier (ATT).
A special thanks goes out to ATT for looking the other way (purposefully or inadvertently; I don't care which it was :-) ) when it came to holding the archaic line of mobile application control. Apple and ATT broke the mold, and we'll owe it all to them five years from now when pressure has caused the other carriers and handset manufacturers to get on board.