Chess Opening Puzzle App I like chess puzzle apps. But they all focus on the end or middle game.

The reason is clear: In the opening there is no single truth.

But there is some common sense what's good and what's not.

Is there an android app which help me train the best opening moves?

I found some apps for openings, but they work like this: First you need to choose the name of the opening, then you train.

I don't care for the names. 

I want to see a chess board and then it is my turn to do the next move. 

I don't want to choose a particular opening first.
GM Nigel Davies has a training DVD on opening tricks&amp;traps, I'm sure you will like it. 

http://en.chessbase.com/post/nigel-davies-tricks-traps-vol-1

Also, in lichess.org, there are quizzes for finding good development moves in openings, I recommend you to take a look. 

By the way, lichess.org can be used by it's Android application, if you don't want to use it from website.