What languages are used to develop Android? And what is the difference between Android and iOS apps?

Answer 1

Java is used but you can make some using C++ with a special lib (ndk).

Answer 2

Java is most popular, but there are really numerous ways to develop Android apps, since for what I can tell, you really only need a compiler that recognizes the SDK and the Android SDK, which you can download and install for free from Google. There are bounds of info on the subject Via Google. Also, I don't know much about iOS developing, I know people use different means to build the software, different SDK, etc.