For sure, it wasn't conceived in a vacuum. Apple's existing IP would have provided essential pieces to make it possible. I've only owned a single smart phone s

For sure, it wasn't conceived in a vacuum. Apple's existing IP would have provided essential pieces to make it possible. I've only owned a single smart phone so far, and it's an Android device. But I've noticed that Apple's devices have smoother interfaces. I've wondered how much of that can be traced to platform factors, and how much is simply execution and polish. And whether the OS design, and the difference between ObjC and Java, play a significant role. My impression was that Java was a dog, but it seems to run pretty well on Android. It's possible that with the meticulous attention to detail of a company like Apple, Android could be made as responsive and smooth as iOS. Or, maybe, platform issues make that virtually impossible. It would be more technically intriguing to think that native code and Quartz are decisively better, but I'm leaning toward the more boring explanation that Apple just worked harder on the UI, and expended the effort to do all the little things right. The basis for my opinion is the observation that true explanations are more often boring. I'm not very expert on graphics, but I've had a suspicion that dedicated graphics hardware makes iPhone-type devices possible. Highly-integrated and highly power efficient graphics hardware was only just becoming available when the iPhone was in development. And, as you mentioned, the software layers to take full advantage of it in a GUI wasn't something you could just take for granted.