Android coding style and your Android Studio

Android doesn’t have an official coding style, but a damn good place to base your code style on is the official Code Style Guidelines for Contributors.
While this is a very comprehansive guide, you would probably still need to embrace and learn the recommended Java code style in your code.

Android studio integration you mentioned?

Decoupling your Android code

Android as a platform offers a lot of different components to be used around. In a single Activity you might find yourself with a stack of Fragments, Views, Model data, adapters, Action bar actions, View actions (click), context menus and more.
Aiming to combine them all in an elegant way that will guarantee you with flexible and modular code will require you to “decouple” them from each other. That way, you will have the opportunity to re-use them, and make future changes easier.

Styles, Themes and dimens = CSS ?

There are many approaches to how to implement the entire world of styles themes and dimens,

one approach is to use it like CSS - where every View in a Layout is set with his own style and dimen.

Locale language and the ISO-639-1 fix

If you ever want to have a "standard" naming convention for communicating Language code with a 3rd party service, you will want to have a common interface for that. For this purpose there's ISO reference called ISO-639-1 which Android is using.

So every thing is cool and the ISO can be used safely? Not 100%.