Really? You couldn't go through the settings one time and see it right there in "general" settings Himanshu? Come on man.. It's just as easy to find as it is on any other platform.
And I had also been using Yahoo, Gmail, and Outlook Mail on my 3 previous phones (920, 1020, and 1520) and didn't have any problem adding accounts and contacts. Again, just like any other platform. The thing with Yahoo for me though, what made it easy, is I had already imported my Yahoo contacts (and my Google/Gmail) into Outlook before ever getting the new iPhone. So it was a seamless transition for me.
iTunes... Yeah, I get it. I can see where it can be confusing for some. Like is said though, I don't use it for anything other than the rare occasion where I want to add some custom ringtones to the phone. I think I might make a video tutorial, demonstrating how easy it really is to add a ringtone to an iPhone. Then I'll upload it to my YouTube channel and share it with that guy over @the verge.