IOS and Android started about 6 to 7 years ago. Just the two against each other starting out. Windows Phone 8 is fairly new and is up against to other platforms that have been established. WP8 has a bigger battle to overcome than IOS and Android when they started. I can remember my first Android device, Not very many apps compared to Apple.
I had a Iphone for a few months but didn't like it much so I bought a Android phone. I was with Android from the start to last December. Even though the app selections is more I got tired of the laggyness of Android and went with the Lumia 1520 and love it. It has not been laggy at all since I got it. I did get one with the touch problem but I am getting another 1520.
At this point I will remain with Windows Phone.................