Convert my keyboard inputs to android phone

So, i have been learning to create games and apps for android phones.
And i already created a small portion of my game,but i have few doubts.

1.My games works for pc inputs,how will i convert wasd to touch input?
2.Is it possible to do with unity without any asset from the asset store?
3.If there is an asset which makes my work easier can you please suggest me that?

you can make your own android controller

http://imakeinternet.com/unity-2d-tutorial-screen-player-touch-controller/

or try mobil joystick from standart asset Unity

I’ve tried the mobile joystick, and every touch juts acts like a left mouse click, no matter where I touch on screen. Is there a tutorial anywhere on how to set this up? Using Unity5

I heard a lot about dansgametools in asset store, any idea about it?