Mobile Coding Apps?

Hey all,

So I decided to go back to school and picked Graphics Communications as my major. I know down the line I will need to learn how to code things. For web or game design. I want to learn each coding path if I can.

For a complete beginner to this, are there any recommended free android apps that would help me get started? I’d like to get ahead and start learning now so I have some understanding when those classes role around. There are so many apps, I’m not sure which one to pick!