Language advantages Android/Iphone

Like for features. Can C# do anything that unityscript or boo cant vice versa. I am trying to make and android/iphone gyroscope augmented reality 3d game. Also i heard iphone doesnt support unityscript, and dynamic scripting is off on android. Without dynamic is unityscript harder than c#. Also which language takes longer to learn. Will i be able to do EVERYTHING that C# can do in unity script. Just like the end product, im not talking about not being able to use visual studio. And one more final question (sorry for troubling you guys). Are there like apis or something that allows me to code in JAVA or Objective C for android/iphone developement. Thanks so much for the help!