The advantage of using a single language is that, for each single app in all the three store, you have to change a single codebase and not to make 3 different changes in 3 different codebases just because each of them require its own language (and then its own specific libraries). So you have surely to spend the time to sort the libraries, but it is a one-time problem. After it, you can just use them without problem in all your projects and you really can focus on your idea

Put all the code in a good ui/codebehind separation framework like mvvm, and you are happier than ever.