What is the best decision for Android, iOS, and Windows Phones

It is a very important choice to make, for your smartphone more often than you think is going to be your only friend in need.

When I started my research I had three options:  iOS, Android and Windows Phone. I asked myself these questions, and tried to answer them. My decision was based on the answer to these questions. 5 reasons your laptop displays not-charging when plugged in..

What am I going to use my phone for, the most? 

When you go to your pocket to get your phone, what is it usually for? Buy a phone that is good at this, for this is what you will doing most often. Android if you want to Facebook / glance at numerous widgets / want to know what airplanes are over your head. Windows Phone if you have simple needs and need them to be met rather elegantly.

What I want my phone to be?

What are the superpowers your phone must have? If you want your phone to be Iron Man who uses jet propelled propulsion boots to fly around, have JARVIS map civilian faces using weapon ownership features, you are looking at Android. But, if you want your phone to be superman, fly around with a push to the ground, shoot simple red lasers from the eyes, you are looking at a Windows Phone. A Windows Phone needn't work down in the lab for hours to be a superhero, it comes as one, albeit a normal one.  How I Root Samsung and Other Androids With Chinese Version Kingroot Without PC 

Similarly answering the following will put you at a better position to take a decision :

1. After using my phone for 6 months, what will I expect from it? When the honeymoon period is done with, what would you expect from your phone? 
2. What are my app requirements? What 3rd party apps do you need? Without what, would your phone be useless? 
3.  What platform do I generally use otherwise? What OS runs on your computer? Who is your primary email provider? Where cloud storage service do you use? 
4.  How much time do you have to customize your phone? Can you spend an entire Sunday customizing your phone to be the way you want? Or, all you have is an hour to play with the options?
5.  Do you trust the people behind the OS? What do you think about the OS's developers? 
6. How often are updates released, and how do you get them? It is highly likely that the phone may not have something you want or need. It that case, you wait for updates from either the OS vendor or developers. How active are the people at helm? 
7. Did you fall in love when you held one in your hand? When you see one at the store or with a friend, do you feel like taking it home?

If you are still confused :
Give points to these questions by importance, give scores to Windows Phone and Android for each question, multiply the score by the imp. points and finally choose the winner. For sometimes, numbers can help you make a choice.