iPhone is so popular and sold so many in short time because iPod is very popular item and now people like the idea having phone and ipod together in 1 device.
So iPhone is hot item now since iPod is already a hot item and both in 1 make it hotter item.
It not really because of the "cool graphics" on iPhone. Even Windows Mobile can have same "cool graphics" like the iPhone.
I have a CIngular 8525 which I already installed and customized software that it almost look and feel like an iPhone. I prefer WM becasue of customiation and avaibialty of third party software for it. I also like the high speed 3G phone network and to be able to connect it to my laptop.
Here a video of Tytn II (Same hardware as AT&T Tilt) with Windows Moibile 6 that is customized with software to look and handle like iPhone. My 8525 almost look like it too. Many of the software are free to download and few only cost 5-10 dollar to add.
YouTube - HTC Tytn II with look & Feel of Touch Flo
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