How to develop iOS app using Xamarin Studio on Windows?
Currently it is not possible to develop for iOS using Xamarin Studio on Windows.
If you want to use Windows, you can use Visual Studio.
If you want to use Xamarin Studio, you can do so on a Mac.
Note that you will always need a Mac around, even if you're using Visual Studio.
While not specifically answering the question, it should be noted that it is possible to develop for iOS in Visual Studios using a connected Mac as a build host. This connected Mac could either be through the network or can even be a VM running from your Windows machine.
We can use xamarin studio in Mac OS only. If you want to use xamarin in windows you need to download xamarin plug in to visual studio from xamarin.com. Also you must need Mac Os as virtually running on windows for debugging and seeing output. User interface design should only performs on Mac OS Xcode SDK. So only we need Mac OS virtual machine on windows. In visual Studio IOS project file having .xib file (i.e) Xcode Interface builder, in that file only we need to design user interface configurations using xcode on Mac OS.