Auto walk

Can you post any code for how you are handling the character?

It sounds like what you want to do, is play a looping walk animation, while making the character continue to translate in a direction.

I don't know the android inputs, but it would be something like this -

  var speed:float;
  function Update() {
     // Test for Left Input - Else Assume Right
     if(left){
         transform.rotation(0,180,0);
         animation.Play("walk");
         transform.Translate((Vector3.forward * speed) * Time.deltaTime);
     } else {
         transform.rotation(0,0,0);
         animation.Play("walk");
         transform.Translate((Vector3.forward * speed) * Time.deltaTime);
     }
 }

All of this is assume this is in the script attached to the object, the player. As well as the Y axis being vertices, rotating 180 if not facing that way currently. I haven't tested this, there might need to be some additional checks, like if the character is already rotated, or if the animation is currently playing. This also assumes that Vector3.forward will give you the direction the model is facing, assuming it was imported right and the prefab was created right. If it was imported wrong, you can rotate the object inside the prefab after making it a child of a empty game object. The Time.deltaTime will make sure it translates forwards at a constant speed regardless of frame rate. Everything is inside of the Update function so that it runs every frame to keep the character moving. You will need to add conditionals to break out of this action if the character - jumps, stops or any other action.

Everything above is in JavaScript

Without code posted, it is hard to answer these questions. Good Luck.

what he's trying to explain is the animation similar with the running game genre such as temple run, subway surfer. etc