Thanks for the reply.
Your reply is really informative. But if you look at the people who is developing for Mac, we really get jealous. They are making thousands of dollars. And why not, if we make a good apps and we also can make money like them. I heard about the story about learning Objective-C is really tough. That is the hardest part I believe we should take.
And also, the sale of new ipad for the first week is over 3 millions. So we can think them as potential customer. What I feel the microsoft marketing is fading away and apple is emerging on top.