I have always found terms like user friendly and intuitive, very interesting. If you stuck a smartphone, WP, iOS or Android, in front of someone who had never seen one before, what would happen. Even that is dependent on prior understanding. If they had seen a phone before and had an idea what that was for probably they could muddle through making a call. Without some concept of what the device could do, how would you discover how to do it. Discoverable. Now that's a more interesting concept. There is even more than one aspect of that. There are those things you expect something to do, but need to figure out how. There are those things that you don't even know it can do, and should run across somehow. When you get right down to all three OSs, are basically the same. You click an icon that launches a function/task you want to do, then tap a button at the bottom to get back to the list of app icons. Outside of that basic functionality are the differences, and those things that are difficult in one, if you are used to the other. Given you feel the need to close an app, how the heck do you discover how to do that in the three OSs? How about deleting/uninstalling an app? Switching between running apps? Is any one easier once you know how? Are the others less 'intuitive', if you have been using one for a year? I might say that iOS may be easier as an out of box experience for many because it has so many fewer options. You have screens of icons, that's it. You don't have all the Widget options of Android and the Live Tiles of WP to configure. You get a new app on iOS, it's on the screen, simple as that. In my mind, that gets old fast. I want my device to do more, and it can. Actually all of them can, but all of them may need some guidance as to how.