Say what you will about the iPhone, but I think this is the first phone that was designed with user interface as the primary goal. I tried an emulator of the QTopia GreenPhone yesterday. While the concept of an open platform for a phone is incredibly sexy, the user interface is close to unusable. When I tried to do something simple like create an event in the calendar, I found the experience was absolutely abysmal. (I mean, really, when I create a calendar event, my first thought isn't about what timezone it should be in). The GreenPhone demonstrates the company is more focused on the technology (getting QT working on a phone, which is laudable) than on how someone would interact with that technology on a daily basis. I found myself using the keyboard (the computer keyboard, mind you, not the phone keyboard) to complete the calendar entry because it wasn't apparent how to complete it using the phone pad. I had to resort to a peripheral that wouldn't even be on most shipping models (if at all) of this software to make it work. There's a rumor that Palm hired someone specifically to count the number of taps one would need to make with the stylus to accomplish a task. If mobile phone companies are serious about competing with Apple, which is synonymous with creating an excellent user interface, they'll be wise to hire someone to count the number of key presses and clicks required to complete basic tasks. Any phone that behaves like it requires an external keyboard to make it work properly (and pretty much anything based on Windows Mobile fits in this category) had best rethink their interface in a hurry, or face being marginalized when the iPhone comes out. Much like the MP3 market became the iPod and everything else, the phone market will quickly become the iPhone and everything else.
You have been warned.