In Android Play mp4 video as a background intro video in your app like latest freelancer app plays it on their intro page of android app.

activity_main.xml

  <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/home_container"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >
    
    <com.example.videointro.IntroVideoView
        android:id="@+id/introVideoView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />
        
  </FrameLayout>

IntroVideoView.java

package com.example.videointro;

import java.io.IOException;

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.media.MediaPlayer;
import android.os.Build;
import android.util.AttributeSet;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class IntroVideoView extends SurfaceView implements
		SurfaceHolder.Callback {

	private static final String TAG = "INTRO_VIDEO_CALLBACK";
	private MediaPlayer mp;

	@TargetApi(Build.VERSION_CODES.LOLLIPOP)
	public IntroVideoView(Context context, AttributeSet attrs,
			int defStyleAttr, int defStyleRes) {
		super(context, attrs, defStyleAttr, defStyleRes);
		init();
	}

	public IntroVideoView(Context context, AttributeSet attrs,
			int defStyleAttr) {
		super(context, attrs, defStyleAttr);
		init();
	}

	public IntroVideoView(Context context, AttributeSet attrs) {
		super(context, attrs);
		init();
	}

	public IntroVideoView(Context context) {
		super(context);
		init();
	}

	private void init() {
		mp = new MediaPlayer();
		getHolder().addCallback(this);
	}

	@Override
	public void surfaceCreated(SurfaceHolder holder) {
		AssetFileDescriptor afd = getResources().openRawResourceFd(R.raw.intro); // your intro video file placed in raw folder named as intro.mp4
		try {
			mp.setDataSource(afd.getFileDescriptor(), afd.getStartOffset(),
					afd.getDeclaredLength());
			mp.prepare();
		} catch (IOException e) {
			e.printStackTrace();
		}
		android.view.ViewGroup.LayoutParams lp = getLayoutParams();
		
		int screenHeight = getHeight();
		int screenWidth = getWidth();
		
		// this plays in full screen video
		lp.height = screenHeight;
		lp.width = screenWidth;

		setLayoutParams(lp);
		mp.setDisplay(getHolder());
		mp.setLooping(false);
		mp.start();
	}

	@Override
	public void surfaceChanged(SurfaceHolder holder, int format, int width,
			int height) {
	}

	@Override
	public void surfaceDestroyed(SurfaceHolder holder) {
		mp.stop();
	}

}

MainActivity.java

package com.example.videointro;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
	}
}